I have to say that I used to favor the Xbox 360, but in the past year or so, I've grown to like the PS3 more. It is more powerful, but I think in terms of games, the two systems are pretty equal. The Blu Ray is a huge bonus, IMO. Also, the media apps and the design of the UI is easier to use and more refined on the PS3 as opposed to the Xbox.
With the most recent update, Microsoft has borked the dashboard. They've made it more easily navigable but only in terms of Kinect. It's a step backwards in all other areas. It's clunkier to use now, there are ads integrated into it, and it's slower than the XMB on PS3.
Also the Netflix and Hulu apps now appear more washed out for some reason. The new Netflix app is crap compared to the one before. You can't pick episodes of TV series unless you launch whichever show first. The rewind and fast forward features are not as good as that on the PS3, and it's not as easily navigable using a regular controller.
The only plus side to the Xbox is that it has arguably more games, some of the cross platform titles play better on the Xbox, and you have Xbox Live, which is admittedly a better online service for playing games than the one implemented on PS3. The only caveat is that you have to pay for Live, which is now $59.99/Mo.
IMO you get much more for what you pay for with the PS3. The only question you should ask yourself, is which console more of your friends have. That should be a primary deciding factor.