I downloaded both demo versions of Burnout Paradise for PS3 and Xbox 360 today. I compared them using a Samsung 56" TV both running at 1080i accross HDMI as I don't have time to move them to my room to test them on the 42" LCD for 1080p comparisson. Here are my conclussions:
-both versions are very very very very identical visually. I must have flicked the tv/input button of the TV remote today a hundred times to compare and I can't see anything different between the two versions appart from different brightness/contrast. The method I used to compare is to drive into the same place and do the input changing.
-I noticed some very slight framerate slow downs on the PS3 version when everything gets a little crowded and fast, like when you intentionally drive into traffic head on, although it is very very unnoticeable.
-The game is a definite must buy whether you own it on the PS3 or the Xbox 360.
OK I rechecked and rechecked again. Apparently, the Xbox 360 version also has the slight slow down if you try doing a head on w/ incoming traffic. Maybe it just a matter of circumstance when ths slight slowdown appears. IE: different place and traffic conditions.