You guys are forgetting that the Playstation 3 has over double the processing power then that of the Xbox 360. What the developers have managed to produce within the limitations that come with the Xbox 360 and the short development time is far better then that I have seen on the Playstation 3. Forza 3 is on par with GT5 and has proper crash physics with destructible panels, a in car view and look what little processing power they have to work with unlike GT5.
Turn 10 have made 2 AAA titles (Forza 2 and 3) in the time it has taken Polyphony digital to make 1 and they still aren't finished.
Besides the PC is the graphical king. What you smoking?
Heres the link to the official trailer.
http://forzamotorsport.net/en-us/media/videos/default.htm?mediaid=120#/video/120/