I only have an 8800GT and this runs better than D1RT even at max AA! I'm liking the gameplay, too.
I went in expecting a DiRT style game but on tarmac with DiRT equalling frames.
What I got was basically an exact clone of DiRT but on tarmac rather than dirt, even down to the same style loading screens and everything, but what I wasnt expecting was DiRT style looks with solif 65+ FPS... they have definately fixed something there.
I went in expecting a very arcady racer, and this is exactly what I got. So actually, I like it. Some things need to change, like moving that dialogue box in network games right out of the way (currently sits on the end of my bonnet! cant see left hand apex's).
Bottem line, very arcady, lots of fun, exactly what I expected