*These are only personal guesses, nothing to do with reality. I am sure gog will offer great surprises. :)
Gog has an agreement with the publisher of these games but there may be exceptions (like more than one company have the rights etc)
Here is a list of my guesses for the upcoming games:
(from most probable to least)
1- Flatout 2
2- Unreal Tournament 2003
3- Planescape: Torment
4- Baldur's Gate series
5- Carmageddon series
6- more Colin Mc Rae Rally games
7- more TOCA games
8- Jazz Jackrabbit series
9- Alone in the Dark series
10- Sudden Strike
11- Robin Hood: The Legend of Sherwood
12- The Lost Vikings series
13- Star Trek games
14- Virtual Pool series
15- Pro Pinball series
16- Micro Machines series
17- Europa Universalis series
18- Rails Across America
19- Pete Sampras Tennis series
20- Celtic Kings: Rage of War

i hope your list is incorrect, because there isnt much on there i would buy or dont already have in my collection.

AFAIK it wouldn't make sense to add Unreal Tournament 2003 to the catalogue since UT2K4 basically is an enhanced UT2K3.

Why do you think they will get the EU-series? While it is not impossible I highly doubt it considering that Paradox Interactive (the dev) already own a platform for digital distribution, where they sell all their games, and others.
But of course, as I stated, it is not impossible. Perhaps then considering that they share a similar philosophy regarding DRM as GOG, at least about the games thay themselves have developed. And other aspects.

I would get excited about the Pro Pinball series. These were the best pinball simulations ever made. (Even going back to Night Mission pinball on the C64, and the Pinball Dreams/Fantasies series on the Commodore Amiga.) The Web, Timeshock, Big Race USA, Fantastic Journey. I spent quite a few hours playing these with my nephews, or just racking up high scores on my own.
I already bought the whole series twice (The original release, and the version that's compatible with XP), not including the versions for consoles. The Web and Timeshock were available on playstation one. I would buy them again from GOG just to play them without the CDs in the drive.
These would make perfect laptop games.

Pete Sampras Tennis? WTF?

...and we've got Thursday, 8:58 Polish time, so only 3 hours left... Do you think we will see an update in "coming soon" section today?