Rainbird on 01 November 2009
First of... 
Digital Foundry
Secondly, as this piece points out, Turn 10 and Polyphony Digital have different development philosofies, where PD will more often than not focus on graphics, where as T10 are more dedicated to adding gameplay functionality.
So while PD is playing catchup with T10 in terms of gameplay, T10 are playing catchup in terms of graphics, but it's pretty hard to judge just what the final score is before GT5 is actually out.
But I must say that I was quite astounded to find that GT5:P runs at full 720p and has 4xMSAA.
