Gorman
Author Level
Thanks to Valve any game you see on Steam is also available for PC and Mac.
Although steam has brought a lot of Opengl based games to OSX this does not include the massive library of Direct X games.
Only a small fraction of the steam library can be played on OSX. I hear that plans for a Linux steam client were scrapped but its the same story.
Direct X = 95% of all games = Windows only.