Offtopic: Did OnRPG get another wave of new users? lawd.
Ontopic:
If you're going to be playing online a lot, get the Xbox360.
If you're going to play offline more than online, get a PS3.
It simply comes down to that, as well as what type of games you like.
Sure PS3 has the Blu-Ray player, but I'm pretty sure more than half the PS3 owners don't use it for anything but games.
Xbox360 just simply has better online than the PS3. If you pay for something, you're going to get more out of it.