I would really like to that game on www.gog.com. Any chance of something like that happening, and if so when?

It's possible that they may eventually come here (other DD services offer them so game rights are not in limbo like is the case with many other old games) but first GOG would have to convince 2K Games to offer it's games here and them to allow GOG to sell X-COM games. It's pointless to ask if and when as even if GOG staff would know something about it, they are not in position to reveal any details about ongoing negotiations.

Yep, a lot of the Microprose games are controlled by 2K these days, including X-COM and most (all?) of MPS Labs' games (Civ, Col, Railroad Tycoon, Pirates, and so on). But I certainly see no reason why 2K wouldn't come to GOG at some point, TBH I'm pretty surprised they're not already here.

Gamersgate has the old X-COM series (Enemy Unknown, ...) for 15€~20$ which consists of 5 games and also DRM free. I guess one problem is the pricing scheme, doesn't fit into GOGs current pricing model.

I got my copy of X-Com on steam before I was aware of GOG.
edit: typo