Indeed.

edit: I wouldn't know what the hell 2K said though because I didn't buy the game from them. I bought it from their authorised distributor.

It's somewhat random, it's based on a chance calculation of rank + will, however that is built on top of a calculation that checks how many psi's you already have. Your chance of getting more psi's goes down significantly with every Psi you get. The first one having the best chance obviously.

Wasn't the biggest fan of EU, but I got the itch to try it again. But I wanted to mod it due to not liking some of the design decisions in the game that can be changed.

Turns out, when they put out EW, they put out a patch for EU...Which modied tons of files for seemingly no purpose, breaking mods. So the mod makers have focused on EW support. There's no way to roll back the game (thanks Firaxis and Steam), so for people like me who just have EU, they can't use any mods whatsoever. I'd just buy EW even with my misgivings if I had any money whatsoever.

So that's fun.

So eventually I gave in and got myself a copy of EU. I still think the old X-com were better, but it's certainly a fun game.

So what do you guys think of the expansion? Any notable gameplay improvement? Bug fixes?

Depends on how much you enjoyed the base game. XCOM:EW adds quite a few maps, the two new soldier options add a bit more oomph to your team (though meld is always in short supply), the new aliens do pose an increased threat (at least until research picks up) and there is another mini story arc that gives you a few extra soldiers.
I do personally recommend getting the expansion, but you have to decide what price point suits you.

The bugfixes should be included in the base game as well from what I recall.

Yes, I did browse through some reviews and watched some let's play, so I think I have a rough idea of what the new content is. However, they were all very vague on gameplay and balance, which is what matters the most to me.

As for bugs, I don't know what they have fixed, but my game tends to crash a lot when my laser-equipped soldiers react on overwatch. Google brought up reports of the same bug dated 2012, so I guess I'll have to learn to deal with it.
I think I've also spotted teleporting aliens for the first time today, although that worked on my advantage (saw two crysalids coming down from a bridge at the end of the alien turn, but apparently they didn't notice my squad, and on my turn they just vanished. One turn later they reappeared back on the bridge, moved, this time seeing my squad and engaging, but they effectively lost the previous turn).

I'm liking the game overall, I don't agree with many design decisions but it's still fun. My main gripe with it is how it handles spawnpoints and patrols, especially on terror/abduction missions which tend to have a crapload of aliens way too close to the starting point. I'm having a really hard time not triggering a second or even a third group in the first few turns, and I don't think I'm that bad at positioning.

Teleporting enemies seems to have been fixed in XCOM:EW, since it is possible to have a soldier being able to see the aliens but the aliens unable to see the soldier (ghost armor, mimic skin, etc) Last soldier should never dash. Move once, and cover the rest of the soldiers. A last soldier dashing can easily wipe your squad, especially if he triggers 2 groups. And don't be afraid to skip civilians, you can usually save more than enough.

Wasn't a fan of EU very much. I think it was full of bad design decisions and overhyped promises. I'm also one of the people who felt the game just flat out cheats with it's RNG rolls. And for a game that tries so hard to be tactical, it's borderline insulting.

That being said, I grabbed EW on a whim, and love it. It doesn't fix 90% of the things I disliked about EU, but it improves upon what EU had a hundred fold. It's definitely a "more is better" approach, as you can build gene modified soldiers, mecs, and there's more missions and variety in the game now. Exalt's fun, but ultimately not that great addition but it does add variety to the game. YOU CAN TURN OFF THE ANNOYING TALKING HEADS WHEN STARTING A GAME~! I can't express how much I hate Dr. Vahlen.

The bad design is still there though. But for that, I just use Toolboks. With that you can do a variety of things, such as making panic not continent wide, move the alien's "free turn" to AFTER your turn, so they don't get an interupt movement action, remove the automatic camera movement after a soldier's turn, and other things like that. Some of the features aren't 100% ported to EW, but most of the big ones are.

EW makes EU a good/great game despite EU's numerous flaws IMO.

Edit: Oh, and I still have to mention that Firaxis STILL requires the game to "phone home". So any kind of modding is very difficult to do. Toolboks gets around that, but most mods don't. They claim it's to stop cheating in Multiplayer, which is just freaking lame.

You do know that the only RNG cheating that happens is in the player's favor, right? On easy (and maybe normal), you can't miss 3 times in a row. Third shot will always hit, no matter the percentage.
That is the extent of the RNG cheating, I think I should be able to find the analysis if you want me to.

It won't change first hand experience of my soldiers missing 90% hit percentage shots, while the aliens hit my soldiers in full cover at will; though I suppose that could be observer bias. When the game arbitrarily limits your squad size, every missed shot at high percentage followed by a shot in cover is incredibly frustrating.

The usual aliens to make these shots are thin men with light plasma (so 65-70 base attack plus 10 from the weapon, -40 for high cover means a 35%-40% chance to hit) and mutons with plasma rifles, who also have a high base attack. Add to that the fact that a plasma shot will hurt (a lot), and ghost armor with the +defense seems an excellent idea.

2 links for further reading.
Is XCOM truly random?
Demystifying the XCOM: Enemy Unknown Psuedorandom Number Generator.

Some good reading there. What I think would help with the feeling of unfairness would be a squad size increase. In the original Xcom, one soldier doesn't really matter. In fact, Rookies are more or less meat shields. In the remake, since you can only field a maximum of six soldiers, every soldier death can cost you a mission. And when you just happen to get luck screwed, it makes it all the more painful.

I don't even get WHY they restricted it. In the EW base mission, you have many more soldiers you can command. So it clearly wasn't a game engine restriction.

Does that count as global bug fix or a feature of EW? Pretty sure I saw them stop at the end of the alien turn: they had no more movement points. And I could still see them while the camera panned to my heavy as my turn began. But once I sent a scout to lure them out they were just gone. I wasn't dashing. My squad landed at a crossroad, only soft cover in sight, one car on the left road (and a van with full cover, but that was too far) and two on the right. Since I had to restart that mission several times because of crashes on overwatch, now I know that if I had moved at max range in both directions, I would have triggered 2+3+3=8(!) crysalids. There was also a floater patrol that would usually reach my position within 4-5 turns, and lots of civilians eager to be zombified (at least 2 per group of crysalids).
I say that's really not a lot of room to maneuver. The map isn't small, no need to put all that crap near the landing zone.

Thanks, I suppose that answer my question. I want to finish the campaign at least once before resorting to mods, but I'll keep them in mind.

I think they just wanted to make gameplay faster than the old times, the whole game seems to be designed with that in mind. Can't really blame them for that, but yes, 4 soldiers as the basic squad side is annoying. They could have at least made the upgrades cheaper.