If you actually get all fanboyish about a video game system, you are officially retarded. They both do some things well, and both have some fantastic games(Uncharted 2 is fucking amazing, by the way). Trying to assign value to one over the other, to validate ones own choice is so ludicrous, I can't even begin to fathom it.
The systems are so close in terms of actual, usable processing/graphical power that comparison pics/vids become near pointless. Whoopety crap, the PS3 can do more floating point operations, and the 360 has double the memory bandwidth.
Yes you pay for Live service, its also heads and shoulders above Sony's offering, which you can't really complain about because its free. Live offers the more user-friendly experience, better messaging, better partying, and general ease of getting a game started. Sure, I would prefer it be free, but I have no issues affording the 50 bucks a year(30 if you know where to look).
The only palpable knock against the 360 is the god-awful RROD, which would be compounded infinitely if a solid warranty wasn't offered. Microsoft extended the warranty to 3 years to cover RROD, so even though its a pain in the ass when if/when it happens, you're not just screwed. Which is more than I can say about plenty of other video game systems I've owned (PS1 wouldn't work unless it was sitting up sideways, Xbox DVD drive failed but I installed another, PS2 DVD drive failed twice, and I never bought a third).