From my experience, XBox has a larger community (of players), therefore making it more fun to play with other people while PSN has a smaller one. And I think to play XBL you need to pay while PSN is free. Plus, XBox has so many games that are "made" for online multiplayer.
90% of the games for ps3 are made for online too.
ps3 gamer tag:drift_supra add it
89 conquest TSI
TRACTION CONTROL IS FOR PUSSIES.