I don't think we'll see a mass delisting considering no Bethesda games got delisted after the buyout, but I'm honestly expecting that we won't get anymore Activision owned games here.

My only hope is that Microsoft actually gets on board with GOG eventually and we start getting games that should have been here years ago. (Freelancer, Age Of Empires, Mechwarrior 1-4, etc)

Oh for sure. Until the deal is totally closed, Activision will operate as it is.

I wonder if Microsoft will keep the yearly COD releases. I imagine that if they recover Raven and other that were turned into COD supportive studios, maintaining the current status would not be possible.

I really hope they free those studios though. They could be put to so much good use.

Could be worse. At least it wasn't a Tencent acquisition.

I wonder what this would mean for the current GOG catalog. First Microsoft bought Zenimax and thus became owner of The Elder Scrolls franchise, Doom, Wolfenstein, Arx Fatalis, Dishonored. Now they get games like Call of Duty, Diablo, Warcraft, Starcraft, but also the old Sierra games like King's Quest and Gabriel Knight.
Microsoft already announced they are going to add new and also older games to their gamepass.

MS to appoint Arcane Studios for developing Heretic III, Raven - Quake 1 Remake, id Software - Hexen 3 and Tango Gameworks for Commander Keen 7

It's probably not bad news for the catalogue. Microsoft buying Zenimax hasn't caused the ID/Bethesda games to be withdrawn from GoG, and we still have some of the modern Bethesda titles here (albeit not Rage, Fallout 4, Skyrim or Wolfenstein Youngblood).

As others have said, it might allow unpicking of the rights mess on some older titles, which is great news for everyone apart from people like me that will see the resale value of Wolfenstein 2009 fall!

Microsoft is no longer the most evil company ever in the tech world (certainly never was in the videogame world though they did try). So the only thing that worries me about this is the whole "one company to rule them all" thing. I don't like that... but considering the state of Activision-Blizzard since World of Warcraft released basically, I can't say that any change coming that way can be bad... So something bad, something good. Balance in all things... the universe is a D&D druid, what can I say.

Could maybe possibly bode well for the old games from Activision's resp. Blizzard's back catalogue to be re-released on GoG?
Of course it would need the right people (with a sense for game preservation) making the right decisions, and if that were the case I do could imagine a re-evaluation of, for example Blizzard's back catalogue to go down something like this:

"Alright, on to the old stuff... let's see what we're working with here: RPM Racing, Rock'n'Roll Racing, The Lost Vikings 1+2, Blackthorne, Warcraft: Orcs & Humans, Warcraft II: Tides of Darkness, StarCraft + BroodWar, Warcraft III: Reign of Chaos + The Frozen Throne; Diablo + Hellfire, Diablo II + Lord of Destruction...

Wait a minute... aren't the first two Warcrafts and Diablo + Hellfire available over on GoG? And have been and still are turning decent eurodollars on there, for such old ass games at least?

Why don't we put the original Warcraft III: Reign of Chaos + The Frozen Throne as well as Legacy Diablo II + Lord of Destruction on GoG too, and make them turn the same decent eurodollars as well? And re-release the rest of Blizzard's back catalogue on GoG while we're at it?"

While titles like RPM Racing, Rock'n'Roll Racing, The Lost Vikings 1+2 & Blackthorne have been available for free, if I'm not mistaken, I think there are still quite a lot of people (me included) who'd gladly pay (reasonably) to have them in their GoG library.

Hope they buy Ubisoft and EAgames too.

why?
EA is probably too big for them

So, how does Microsoft expect to recoup their 70 Gigabucks investment? Because I don't expect this to be a move to be payed in a generation or two. What does MS get from this that they could milk out of it?

- ownerships of titles already published and in development. Profitable but not that that profitable. With Steam accumulating distance from Windows I hope to see these games here.

- ownership of the IP. That allows them to create new games. Maybe even try a movie deal or something?

- exclusivity of games on XBox. This could boost sales somewhat on the long run.

- acquisition of talent and expertise. Not a major thing

- moving the existing player base to a single XBox account.

I still feel three zeros short.

yeah strange , clearly overpriced imho, probably insider trading

You won't see legacy Diablo 2 here for the same reason you won't see legacy Skyrim, legacy Age of Empires or 101x other games for which the publishers are charging 4-10x more for a remaster. They simply won't sell a game for $5-10 here if they can sell a remaster for $30-$40 on all the big sites, which for Diablo 2 Resurrected isn't going to be here at all because of newly added DRM / online requirements. Remaster-itus with "enhanced online content" is fast becoming as hostile to 'digital' availability / preservation of classic / originals as DRM itself, and if you want Diablo 2 Legacy DRM-Free then definitely grab it on disc whilst you can (the disc check was removed in patch v1.12).

I don't even see any of this making any positive difference to the GOG audience for reasons mentioned above. Microsoft are no better than Ubisoft when it comes to adding in multiple layers of DRM even to 25 year old games, eg, Age of Empires 1 = Steam or MS Store client check + "All versions require Arxan Anti-Tamper DRM" (Microsoft's equivalent of Denuvo)...

I said it from the point of view of someone who thinks that when MS buys a gaming studio, that gaming company or studio kind of dissapears from existence and MS doesn´t get any discernible benefit from the purchase.