First, I am not here to argue XP vs. Linux.
As you can probably see, there aren't many 'major' games for Linux. There are many great, addictive games that I could play for a while, but nothing of the scale of a Windows game. Why is this? Linux is not harder to program than Windows - after all, SDL makes it somewhat easier! OpenGL (IMHO anyways) is simpler than DirectX, using mainly function calls (no data structures required). Wine solves this problem somewhat - games developed for Windows can be run on a Linux machine, if at 2-3 FPS.
What are your opinions on this? Do you plan to create cross-platform games? Do you think that Linux gaming will take off?