15-35% performance increase in openGL games like Doom3 and Quake 4...I think Nvidia just lost its edge, beat by ATI in DX9 AND OpenGL now.
Not really, those performance increases are only valid when using high resolutions with high AA settings on X1800 XT.
For the mainstream user with his X1800 XL, he mostly will experience performance decreases when using the OpenGL patch. All others cards (X800 and below) are not effected all by the patch. So a last generation 6600GT is still able to beat a next generation X1800 XL because ATI's OpenGL has not changed, it still is useless, only some memory optimizations have been done.