I am a Linux user who also likes to play 3D games, so it's been nvidia only for me for a long time. Now that we will hopefully start seeing some good open source 3D drivers coming out for ATI, I am definitely switching! I just hope nvidia realizes this and follows. So many times after a system software or kernel upgrade, poof, the closed nvidia driver stops working... causing me to have to CTRL-ALT-F1 to a root shell and modify xorg.conf just so I can get into X11 again to be able to fetch the newest driver. What a pain. Having open source 3D drivers for both would be awesome and a complete win for the Linux community.