First, I'm sorry if a topic about this subject has been posted before. I tried to search for it, but couldn't find one, so figured I might as well create it:
The purpose of this topic is to have a place where we can put out your best guesses and speculations of which publisher or developer might join GOG next. This is only for fun, so you don't get a prize for being right (unless someone is in a giving mood). Also, this is not supposed to be a direct wishlist, so let us try to keep it real; it would be good if you could state your reasons for why you think that particular company might be next.
I'll start with my guess, which is Novalogic. The company has had very few new releases the last few years, so posting their old games on GOG could help generate some revenue. They have never really appeared to me as a company who are too fanatic about DRM either, and most of their games look like stuff that would fit excellently into the GOG catalogue. To me, they look like the perfect bedfellow for GOG, and frankly, I'm surprised the two haven't gotten busy already (or maybe they are, and we just don't know it yet!)
Their games include tons of various flight-simulators such as the "F-22 Raptor" and "Lightning" series, along with "Commance" combat helicopter sims. They are probably best known for the "Delta Force" series of military first person shooters though, and not least the cult-favourite "Tachyon: The Fringe" space combat simulator. There's a total of about 20 games in their backlog, most of them released before 2005.
So, let's get the bets out on the table! Who do you think is coming up next on GOG?

Psygnosis

well a high possibility will be publishers who need to balance their books
thq could a viable possiblity !!!!

id
10ids

I live in a little utopia.
So I fear nothing when I say 'Lucasarts' (pre 1997 though).

That's all they will ever release, since they no longer exist. I've got all of them, with Arcanum through a magazine as you mentioned. Wouldn't mind having them here though.

I think Novalogic is a likely candidate (as I think I said in the last thread about this).
Probably not, as Psygnosis was bought by Sony. But I suppose it's not impossible.
But speaking of publishers from the nineties, I think maybe some games from Gremlin would be more likely. A number of their old games were bought by Zoo Digital Publishing (now Zushi Games), another small publisher that could benefit from a partnership with GOG.
As has been noted, they aren't around anymore. Besides, I think the rights to their games are owned by the publishers (Arcanum & Vampire - ActiBlizz, Temple - Atari).

be great to get a verson of Metal Fatigue that actually worked on vista - still can't get mine to work at all :(

Muckyfoot isn't a bad guess. Bullfrog would be made of win, but EA has control of that now.

No new publishers this week. Instead, it turns out that Apogee and Interplay are extending their catalogues. Extending them so far in fact, they reach right into my bank account, removing money.

we getting more of the duke???

Origin!
I'd happily pay for the Ultima games ten times over.
Unfortunately, they're part of the EA behemoth. :(

I can imagine it now...

The Learning Company
The guys that made Lemmings
Titus
Atlus
Microsoft (Hey, it could happen)
SouthPeak Games
EA (If Ubisoft can come to GoG, don't see why the hell EA can't)
id
2K Games
Activision (see EA)
Come to think of it, I see Activision as the most important company to come over because if I don't see a Vista-friendly version of Zork Nemesis and Zork Grand Inquisitor pop up soon I think I will go daft.
In fact, bring all the Zork games. No, bring all the Infocom games. No, bring every damn game with a text parser! Come on, Activision, I know you're holding out on the good stuff! Sitting on all that merchandise ain't gonna do you no good when you have some buyers waiting to get their fix. How do you expect to make a little green on the side? I've sampled your text parsers before, and I have to say, that s**t is primo. You've just been doing so much Guitar Hero that it's beginning to hamper your judgement. So come on, hand over the goods! I'll pay top-dollar for that sweet, sweet command prompt.