gwuinsf saidI have both and my preference is XB360. My main question to you would be whether you own a Blu-ray player. IMO, if you don't, then get a PS3 just for that capability. The other advantage of PS3 is that you don't have to purchase a subscription to play online games as you do with the XB360.
If you don't care about the BD player and you don't play games online then go with XB360.
I also work in the video game biz if that means anything.
Tricky advise, although having a Blu-Ray available is always good you're still buying a GAME console not a home theater system. Considering that you can always get BR player either stand alone or integrated on the stereo system I wouldn't choose a game console based on technology that does very little for the game experience itself.
You said "if you don't play online games then go XBOX360". Bro....WTF?
XBOX live is payed but you get s lot more than what's on PSN, better party game options, better apps, better stability, better security(PSN went down for over 2 weeks and a chunck of the database with user info was stolen by hackers). If you are SERIOUS about online gaming by all means pay the $50 a YEAR, XBOX live is worth, totally worth it.