Okay so i am a Ubuntu Linux user and also loving gog.com (only found it within the last month!).
First question is are there plans to officially support Linux?
Second relates to the first - If you don't plan to, could you add in a WINE "app db" link for games that have one? Any games i have searched seemed to work really well.
Like this one for example:
http://appdb.winehq.org/objectManager.php?sClass=version&iId=13945

Obviously no user can answer your questions, but here's a list of what does (allegedly) work already.

Welcome!
AFAIK, there are no plans for official Linux compatibility.
Also, I don't think they plan to do anything with Wine, officially. But, here's a fan-made thread about games which work well with Linux/Wine. You may want to drop in there.

If GOG doesn't support Linux (they have previously stated they have no actual plans to, but are not inherently opposed to it), then why would they go to the effort to create or link to an AppDB entry? Doing that would imply that they do support the games on Linux, which could create a whole world of support problems for them. Besides, just like most things with Linux and especially with Wine, this is a job for the community, one they have already embraced fully as indicated in the thread already linked by previous posters.