Having both and being somewhat biased towards the PS3, Id say:
Innovative games and unique titles goes to PSN by far
Online communication and System integration goes XBL
community aspect is tied in my opinion, I unlike most people here enjoy home and have made friends on home, lately the updates give to home has made it a greater place to be on. XBL has XBL prime time which currently features 1 VS 100 which is a great community show that pushes XBL high up there, but Home really really does give the community aspect on PSN a huge boost, sadly the integration with HOME and the actual system is not good, therefore I say they are tied. If home had cross game chat(with HOME and PS3 games) and if the game integration was better, I would give the community features to PSN.
