I recently bought a Playstation 3. I haven't regretted the decision even once. I chose the PS3 based on the fact that it can play Bluray and DVD movies in addition to streaming video and playing games. I only casually play games, so the available games didn't play a huge role in my decision, but regardless there aren't any games for Xbox that I would play that aren't also available for the PS3. The Wii I didn't even consider due to lack of games that interest me and lack of ability to play disc-based movies.
PS3 is nice, very nice. It would be my second choice though. Although PS3 doubles as a blu-ray player still I find the games and especially the community, not to mention Kinect on Xbox make it a better console. For me, there is also the tremedous added value and functionality I get from the Xbox Media Center extender. I run a Windows 7 Media Center PC, plus I have a Windows Home Server. I have two xboxes and I use them both more as a Media Center extender than I do for gaming. Nothing comes close.
We have both here, and the Xbox gets used every day while the PS3 gets used only when someone fancies taking a break from Halo Reach, Black Ops or Dead Rising 2 and play Little Big Planet or watch a Blu-ray movie. Indeed, I tend to think of the PS3 as our Blu-ray player rather than a games console these days. The Xbox has by far the better (from the perspective of our family at least) games selection, online gameplay, online community and, of course, Kinect...
I used to always have a PS when i was younger, but converted to PC gaming and found that much better. Now i only really play xbox360 which i bought in March last year, mainly because most of my friends had one but i do enjoy it. Overall, PS3 is probably more of a stable and professional console but xbox tends to be more popular. Personally out of the two i now prefer xbox but i'd rather do PC gaming than either of them as it is much more competitive, openly modded and graphically superior, but i can't afford to upgrade my PC! aha