An interesting comment on Nvidia:

http://semiaccurate.com/2010/05/30/how-nvidia-blacklists-sites-hardware-secrets/

I am not a big gamer but I like a video card that can play a game without spending a small fortune as I have done in the past. It's only DX10.1 and I don't care. I will play any game and that's all I care about. I gave up trying to set 3dmark records a long time ago. I have bought both nvidia and ati in the past but nvidia has screwed the pooch to many times for me.

but the OS is. DX11 ONLY runs on vista or win7, which a lot of us won't get into. If you can bring DX11 onto winXP, your sales will surely shoot.

Otherwise, try think OpenGL.

"Nvidia thinks that the lower price will encourage more people to get into DX11 gaming."

Yes, by buying more ATi cards at better price points.