rgnrk: > 1200 (according to GOG's count, with no hidden games)
Finally someone. I don't know what to think of those other people saying "I've got 5 games on GOG.com, wheee! I've never owned this many games in my life, and I don't think I can ever finish these 5 games of mine! Wheeeeee!".
I currently have 1194 (according to the account library page), and I am not done yet. Yes I am playing them, but not all at the same time. I have even downloaded all those games to an external hard drive (thanks to the gogrepo tool), just downloaded the latest updates to my library yesterday.
On Steam I currently seem to have 438. Somehow they have also accumulated (mostly through some Humble Bundles), even though the only game I've played on Steam for ages is Team Fortress 2 (a free-to-play game).