I say 360 for the games, live system and general interface (although they break on a daily basis ~ i know from experience). However i would also say its a tough competition and PS3 is catching up fast, the games are improving but it still has a few major flaws; the RAM is divided up into 4 parts, a program can only use one of these parts at a time (so it runs multi applications more smoothly but a good program cannot use all of the RAM to burn for itself unless it divides itself up aswell which is well, dumb) and also things like having to come out of games to start a convo with a friend, it just doesn't work.
So in my opinion for the gameplay and enjoyment, 360 is the way to go at the moment unless your looking to the future.