I've owned both systems for a good amount of time (12 months 360, 4 months ps3) and to be honest my ps3 spends most of its time gathering dust. I bought the PS3 for 3 reasons - Ace Combat, Devil May Cry, and Final Fantasy. 2 of those 3 are already after confirming that they're coming on the 360, and to be honest every game on the ps3 (except Motorstorm) has an equal or better equivalent on the Xbox.
Sure the Playstation Network is free, but Xbox Live is €60 for the year... €5 a month... you save more than that a month on games either way. And it's a better service - GTA IV is getting exclusive downloadable chapters on Xbox Live that PS3 players will never see.
I'm going to give my own list of pros and cons by grouping both consoles into catagories...
Technology: The PS3 has more raw power, that's obvious. It also has Blu-Ray which hasn't really taken off all that well (I work in a game/movie rental/retail store that deals in both Blu-Ray and HD-DVDs, and from what I've seen, people don't care about Blu-Ray all that much). Oh, and you don't get a HDMI cable either so you can't enjoy Blu-Ray until you go out and buy one of those. The Xbox 360 has been upgraded to 1080p by a software update so the PS3 no longer has that advantage, and the cable you get with the Premium console (component HD) allows you to take full advantage of that straight away. Oh, and being able to buy a core, upgrade it to a premium by buying a €90 hard drive is a good thing too. As is being able to buy the 120gb Elite hard drive seperately and install it quick and easily on your own without voiding any waranties.
Games: Xbox wins by a huge margin here, simply put, the ps3 has only a small handful. Yes the Xbox has been out longer, but you'd expect more than a handful of sequels after this amount of time. Motorstorm is the only good game I've played that isn't a sequel to be honest. Pretty much any PS3 game you name, there's a better game of the same genre on the 360. Yes, the Xbox is thriving on sequels (Halo, Forza, Fable), but it has a healthy selection of games that aren't sequels too (Bioshock, Chromehounds, Gears of War). Believe me when I say I can argue about the games lineup for both consoles on length, it's part of my job (there's a lot of hardcore gamers in my area that enjoy a good PS3 vs XB360 debate)
Community: Xbox Live or the PSN... touch choice? Not at all. The Xbox Live marketplace... access to all that downloadable content - demos, movie trailers, extra costumes/levels/cars/whatever - that alone is worth the €5 a month. Being able to game online is a bonus. And what a sweet bonus it is.
Price: At this point in time, in my store, the Xbox 360 (premium console only, no special offer, no bundled game, just the console) retails for €359.99. The PS3 (60gb model, again no special offer, no bundled game, just the console) retails for €629.99. The price has dropped in the states, and it is just a matter of time before it does the same here, but really... throw the price of maybe a second controller and 2-3 games on top of that, you can buy a 36" 1080p LCD TV for that kinda cash...
People say that all xboxs experience the RROD, that's massively overrated. And so what if you get the red ring? Microsoft take it, repair it, and give it back in less than a month, for free. It happened to mine, it wasn't that much of a pain to be honest, they picked it up at my door and dropped it back 3 weeks later. The PS3 has a much nastier problem - there have been a number of people come back to me saying that their PS3 is chewing up their games, and I have seen a few fairly nasty discs, they actually have grooves etched into them. Didn't have that problem myself but I'd rather have my console break down and get it fixed for free instead of it chewing up my €60-€80 games.