I can guarantee it's not Activision, nor is it EA. I am very very doubtful that it is Sierra (Vivendi) or Lucasarts. Let's remove those from the list of possibilities, and see what remains of any stature.
Atari is one for sure.

Similar to Valve, Paradox, and Stardock, they too have [url=http://eu.blizzard.com/store/browse.xml?f=c:1,c:7]their own digital distribution store[/url], selling at least some of their games. I would definitely like seeing Warcraft 1 and 2 and Diablo 1 here though, maybe even The Lost Vikings games, and Blackthorne.

Well, that's true. I guess we can't rule them out completely. I'd imagine that we're looking at a more established publisher though. That is, assuming we're definitely looking at a publisher here. They never specified that it was a publisher deal.

I think that someone should tell them that the difference between GBP and EUR isn't that big.

Although in this case Activision Blizzard are actually responsible for the listed prices as they're their own games on their own site. Valve's games on Steam are all priced the same in GBP and USD (I don't know about EUR). It's just that they allow other publishers to price as they see fit.

LucasArts is my bet. Times are mature now....

LucasArts ? With the games they released on Stem? Very unlikely, i think...

Would love it to be Atari as they bought over a lot of companies in their old days so might have a lot of good old titles to sll to us.

It's possible.
For example check the latest games on Impulse:
Divine Divinity
Beyond Divinity
and Oddworld - Abe's Oddysee
(OK. my post is off-topic)

Why not? They can't affort to turn down money anymore. Not to mention Sega has been very interested in the PC platform of late.

I wonder how soon it will take place?

GOG's pricing policy will never meet Kottick's "standards".

I think Interplay, or Bioware, or whoever owns the Baulders Gate series. I actually have no idea who has the rights to that game anymore.

According to Interplay its Atari thats publishing the re-releases of Baldurs Gate, Planescape and Icewind Dale.

Since the deal appears to be signed, I'm sure there will be several releases in good time before christmas.