Opt in beta update for Steam only, according to the wiki.

At least, that's what the idiots on the wiki say. :P

try and have Galaxy do a verification of the game files by going to More->manage->verify/repair that should do the trick as it should have Galaxy check the files and notice that the numbers are off and download the new patched ones.
and the idiots(as you put them) on the wiki are incorrect. According to one of the coders Skiphs(who is also doing the Mac/Linux) ports the update also had minor changes/tweaks to the changes made in 1.3.0.6 so they felt there was no need to go into detail again as they already said what was changed in the notes for 1.3.0.6.

Changelog for update 1.3.0.7 / GOG-8 (added 24.07.2015):

- Mac & Linux support (COMING SOON TO GOG!)
- Several internal changes were made to allow for the support of Mac and Linux.

They aren't incorrect, the beta is only for Steam users:
http://forums.terraria.org/index.php?threads/terraria-1-3-0-7-mac-linux-open-beta.27418/page-8#post-640916 Steam and GOG will both have the finished versions, but only Steam has the beta. What you said and paraphrased does not dispute that fact.

I wasn't talking about the beta, I was talking about how 1.3.0.7 had according to one of the guys on the dev team said there was minor tweaks in the update to the changes done in the previous hotfix and so in his own words didn't feel it necessary to repost the changes that they already posted just with tweaked again attached. So yes they were incorrect as there was more to the update then just rolling out the beta test for the Mac and Linux versions. Just those changes were not major enough to warrant a change log.

from Skiphs himself: https://forums.terraria.org/index.php?threads/terraria-1-3-0-7-mac-linux-open-beta.27418/#post-640547

Changelog for update 1.3.0.8 / GOG-1 (Mac) / GOG-3 (Linux) / GOG-9 (Windows (added 12.08.2015):

- Mac and Linux versions added.

Changelog for update 1.3.1 / GOG-10 (Windows) (added 22 May 2016):

- The Mac & Linux versions will be updated on Monday 23 May 2016.

Features:
- Added Controller Support using Xinput.
- Added Inventory Sorting.
- Dart Traps & all Temple Traps can now be hammered to rotate 90 degrees at a time.
- Added smart interact, making chatting with NPCs, opening doors and using objects easier.
- Cannons (normal, bunny, confetti, Snowball Launcher) can now be controlled by wire and shoot fake projectiles!
- Improved Smart Cursor & made it interact with more items.

Quality of Life:
- Improved Wire drawing to look less fuzzy with multiple colors on the same tile.
- Improved over 1,800 sprite graphics.
- Optimized net messages for tile entities (target dummies, item frames)
- Improved the Settings Menu and added new settings.
- Added new large gem over-head display.
- Improved melee hit detection around slopes.
- You can now use situational building accessories from your inventory and toggle their effects like info accessories.
- Info icons now have a border around them when aimed at (clarity!).
- Improved keybinding options, you can now also bind to mouse 3/4/5.

Items:
- Added Logic Gates (AND, NAND, OR, NOR, XOR, NXOR)
- Added Logic Gate Lamps (On, Off, Faulty)
- Added Logic Sensors (Day, Night, Under Player)
- Added Liquid Sensors (Water, Lava, Honey, Any)
- Added Conveyor Belts.
- Added The Grand Design.
- Added Yellow Wrench.
- Added Junction Box.
- Added Mechanical Lens.
- Added Announcement Box.
- Added Actuation Rod.
- Added Team Blocks and Platforms.
- Added Static Hook.
- Added Presserator.
- Added Engineering Helmet.
- Added Companion Cube.
- Added Gem Locks.
- Added Large Amber.
- Added Weighted Pressure Plates (4 colors).
- Added Wire Bulb.
- Added 12 new craftable Critter Statues.
- Added Portal Gun Station.
- Added Trapped Chests.
- Added Projectile Pressure Pad.
- Added several new monster statues.
- Added Angler Tackle Bag.
- Added Geyser Trap.
- Added Bone Campfire.
- Added Ultra Bright Campfire.
- Added Multicolor Wrench.

Miscellaneous:
- Critters spawned from statues are no longer catchable.
- Highly increased Duke Fishron's "run away" distance.
- Medusa can no longer petrify players directly above her.
- Medusa is now Hardmode-only.
- Added NPC names for the painter, wizard, and skeleton merchant, based on contest results.
- You can now find Beehives in the Jungle - Not the bees!
- Lowered the volume of the Solar Eruption's use sound.
- Torches can now be put on actuated tiles.
- Slimes should no longer be able to go through 1 block high gaps.
- Target dummies no longer benefit from lifesteal or spectre set.

Bug Fixes:
- Fixed Frostbite hiding time left when wet under certain circumstances.
- Fixed Desert Spirit hitbox to match sprite size.
- Fixed NPCs not recognizing kills / interactions properly if they have multiple segments.
- Fixed music boxes not emitting music notes while open.
- Fixed Flesh Grass spreading under Sunflowers.
- Fixed Tally Counter not showing information for enemies hit with mounts or special attacks.
- Fixed player leg skin colors mismatching the rest of the body when in stealth.
- Fixed Seedler not dropping from Boss Bags.
- Fixed popular NPC Housing exploit.
- Fixed Ranger Lifesteal bug.
- Fixed Paint Sprayer spraying over blocks in several occasions that it should not (e.g. grass that gets turned into dirt as a result of placing an object).
- Fixed being on the edge of the underground not counting when spawning dungeon / Underground Desert monsters.
- Fixed teleporting directly on top of a pressure plate not triggering it properly since.
- Fixed Town NPC melee weapons drawing brightly while in darkness.
- Fixed Crimson Heart failing to stand to roll roll around on platforms.
- Fixed tile entities not properly clearing on world clear procedure.
- Fixed Crystal Storm not bouncing its shots.
- Fixed chests without custom names not showing mouse over icons.
- Fixed Wooden Boomerang being unusable when near slopes.
- Fixed Wall of Flesh going above hell and dragging everyone with it.
- Fixed Martian Saucer having invisible / unhittable body parts in multiplayer.
- Fixed Martian Probe not causing Martian Invasions when it should.
- Harpies and Antlion Swarmers can no longer swim.
- Fixed dressers blowing up from explosive projectiles.
- Fixed Gi and Kimono leg sprites being genderswapped.
- Fixed ancient light and fishron bubbles not appearing in expert mode.
- Fixed Werewolf sounds being bugged if used for vanity.
- Fixed Tax Collector not using some of his special chat dialog.
- Fixed infinite flight time exploit.
- Fixed Martian Saucers missing their home planet during the invasion and leaving.
- Fixed trapdoors de-syncing when operated via wires.
- Fixed L shaped housing exploit.
- Fixed minecarts hitting invincible enemies.
- Fixed multiple bugs regarding auto-pause and inventory management.
- Demon Altars should no longer create 'unbreakable' pots.
- Fixed rare "character not respawning" under certain circumstances.
- Fixed background drawing through completely unlit walls in hell.
- Fixed solar pickaxe using a bad glowmask.
- Fixed wall of flesh not spawning in singleplayer under certain circumstance.
- Fixed snow not falling naturally after a player jumps in most cases.
- Fixed paintball gun and confetti grenades being unable to crit.
- Fixed Titanium Armor & Black Belt dodges not working against Moon Lord.
- Fixed animated tilesets touching half-bricks stop animating.
- Fixed yet another duplication exploit.
- Fixed altered worlds getting stuck in spirit release phase under a rare circumstance.
- Fixed Chlorophyte protection in the jungle not being as effective as it should be.
- Fixed right clicking equipment at inventory not granting achievements for equipping it.
- Fixed paladin's shield ally protection benefits not functioning properly.
- Fixed minor capitalization issue in the guide's help text.
- Fixed star in a bottle buff not working.
- Brain of Cthulhu & Eater of Worlds now properly leave upon massacring the player / if the player leaves their territory.
- Fixed issue where the nurse would not heal all debuffs under rare circumstances.
- Fixed double damage popups from other players inflicting harm to themselves via explosives.
- Fixed 'full-screen map' button opening a black screen if map is disabled in general.
- Fixed players being unable to get on a mount if they're too close to workbenches.
- Fixed shenanigans with actuating gemspark blocks.
- Fixed Mudstone Brick having a bad name (Mudstone Block).
- Tiles under Lihzahrd altars can no longer be actuated until the golem is defeated.
- Fixed temporary holes in the darkness when removing light sources.
- Fixed items that cost less than 5 copper always sell for 1 copper , even when sold in Stacks.

Changelog for update 1.3.1.1 / GOG-11 (Windows) (added 31 May 2016):

- The Mac and Linux versions of Terraria will be updated ASAP.

Quality of Life:
- All liquid & logic sensors aside "player above" now allow teleportations.
- Added a third frameskip option for those with high-end PCs who got performance issues in 1.3.1 (current "Off" got renamed to "Subtle", old "Off" from 1.3 is back as "Off").

Fixes:
- Fixed liquids getting frozen in the air until a game restart (hopefully).
- Fixed gamepad instructions getting frozen on virtual keyboard instructions.
- Fixed two duplication exploits.
- Fixed cannons not shooting cannonballs when pulsed via non-player triggered.
- Fixed slightly inccorect display for "player above" logic sensor (was 1 pixel too small in every direction).
- Fixed incorrect text at the gamepad options ("Thumbstick Hotbar / "Thumbstick Cursor Snap" should've been "DPad Hotbar" & "DPad Cursor Snap").
- Fixed training dummies potentially getting permanent invisible corruption.
- Fixed mouse clicks not getting detected until you click a keyboard button on game startup (hopefully).
- Fixed many furnitures breaking instantly when they're placed aboved platform stairs.
- Fixed multiple issues with geyser placement.
- Fixed particles not drawing in capture mode if background is disabled.
- Fixed the Guide's help tips not detecting the demolitionist nor the goblin tinkerer properly.
- Fixed Grasshopper Statue having no recipe.

Changelog for Patch 1.3.2/ GOG-12 (Windows) (added 20 July 2016):

Items:
- Added Bundled Party Balloons
- Added Balloon Animal
- Added Party Hat
- Added Silly Sunflower Vanity
- Added Silly Balloon Blocks and Walls
- Added Silly Tied Balloons
- Added Pigronata
- Added Party Center
- Added Silly Balloon Machine
- Added Streamers
- Added Party Present
- Added Cog Walls
- Added Sandfall Blocks and Walls
- Added Snowfall Blocks and Walls
- Added Snow Clouds

Changes:
- Nerfed beehive-type bees in expert mode
- Significantly reduced count of unnecessary player synchronization calls, which hindered servers with a high player count
- Trees now grow with a “poof!” even when visible on a player’s screen
- Rain Clouds are now craftable
- Clinger Staff can now use platforms as its resting point
- Made improvements to chat tags, and they should no longer break over long lines
- Town NPCs will TRY to avoid falling into cliffs away from their home area

Bug Fixes:
- Fixed XNOR being named NXOR
- Fixed Title text not refreshing from the language menu's use
- Fixed Cooking Pot & Skeleton Lantern (off)'s wrong light display
- Fixed weather not updating on server properly (blame framerate fixes)
- Fixed Grand Design selling for way too much gold
- Fixed Scutlix mount aiming issues
- Fixed Stardust & Nebula Wings having 2/3 and 1/3 extra fly time more than intended, respectively.
- Fixed crashes related to Ice Rod and Dressers
- Fixed cursor showing over an item slot for a frame when closing inventory on gamepad use
- Fixed random bad texture loading
- Fixed Duck hunt exploit
- Fixed Town NPCs spazzing if there's lava underneath them
- Fixed Travelling Merchant not being able to attack at night
- Fixed Extremely long-timed buffs not updating properly in multiplayer
- Fixed Phasesabers in weapon racks creating unbreakable weapon racks
(This fix is not retroactive and will not fix old worlds impacted by the issue, we apologize for any inconvenience - we may add retroactive fix in the future)
- Fixed Team Platforms not acting as viable doors for housing.
- Fixed Ice Rod blocks causing making backwalls invisible
- Fixed “On Fire!” bosses not being extinguished by water
- Fixed Summoner Emblem not having an updated sprite
- Fixed Some configuration settings not saving correctly

That's nice, the NPCs are going to "try" to avoid killing themselves. :P



-Don't kill yourself Dear!

-Okay,I'll try!

Thank you for the update and fixes. I was just wondering as to when I would try out the controller functions that were included in the previous update and now further improvements were made (AI). That'll help when the time comes; at least it'll be harder to lose AI characters while fighting or adventuring.

Huh. Comparing that changelog with the one posted on the official Terraria forum shows that the GOG one is incomplete. It's missing two more Changes:
- You can now use the Sort feature with chests
- After reaching hardmode, you can choose the type of the world's evil when generating new worlds. If you have already reached hardmode, just load any pre-existing hardmode world and it will activate this feature.

Changelog for update 1.3.2.1 / GOG-13 (Windows) / GOG-5 (Mac) / GOG-7 (Linux) (added 22 July 2016):

- Fixed snowfall walls not dropping their item when broken
- Fixed bad chest button cycling in gamepads
- Fixed weighted pressure plates not working
- Fixed party balloon staying in the world indefinitely if its not the first world loaded
- Fixed npc-started parties occuring only for 1 player in the server at random
- Fixed items being equipped when you open a chest with autopause under certain circumstances

Changelog for Patch 1.3.3 / GOG-14 (Windows) / GOG-6 (Mac) / GOG-8 (Linux) (added 09 September 2016):

Features:

- A new weather event has been added, sandstorms! With it come new enemies, new loot, a new soundtrack, and a unique experience in the desert biome!
- Blizzards now have a new visual effect.
- Deserts and the Underworld now have a heat distortion visual effect.
- Dripping sand effects can be found in the desert, and placed anywhere by the player with the Magic Sand Dropper!

Items:

- Added the Forbidden Armor Set
- Added Ancient Horn (Basilisk Mount)
- Added Onyx Blaster
- Added Sky Fracture
- Added Mandible Blade
- Added Spirit Flame
- Added Pocket Mirror
- Added Djinn's Curse
- Added Lamia Vanity Set
- Added the Ancient Vanity Set
- Added Desert Spirit Lamp
- Added Magic Sand Dropper
- Added several new banners
- Added Music Box (Sandstorm)

Changes:

- Sand Poachers now inflict the Venom debuff
- Dune Splicers now have more HP and Defense
- Dune Splicers and Tomb Crawlers may be more aggressive, especially during Sandstorms.
- Added multiplayer performance improvements
- Upped spawn rates in underground desert

Bug Fixes:

- Fixed sliders in the gamepad settings not being "locked on" when dragged around
- Fixed certain textures loading wrong at random, and producing weird artifacts
- Fixed underground desert worms being too rare
- Fixed a number of exploits
- Fixed Portal Gun secondary fire conflicting with Grappling Hooks on Gamepad
- Fixed rain, water, and lava sounds persisting when the game window is inactive
- Drills no longer shoot confetti at supersonic speeds when under the effects of Flask of Party

Thanks GOG. And also thanks to the devs who still update this game!