I've never really understood why people are so adamant to declare a console "better" than another. I believe that each one has certain advantages. Personally, I own an Xbox 360, Nintendo Wii and a Mac, just to clarify lol.
I chose to get an Xbox 360 because of the game collection it boasted. There is no denying that Xbox 360 has an impressive array of choices. At the time, Mass Effect was the big draw to me after seeing a friend play it. (PS3 owners now get to enjoy ME2 and 3 of course!) Also, a lot of my friends had Xbox Live, which made it an even better choice for me.
Anyhow, while that is awesome, I would LOVE to have a Blu-Ray player and free online play (no ID theft jokes please!) like PS3 owners do. There is no denying how sweet that is. Also, PS3 has it's own exclusive titles like Uncharted and Killzone. Again, things I would love to enjoy.
Basically, there isn't a "better" system. Some people could say Wii is the best because of the exclusive titles and motion controls. They aren't wrong either. It's all a matter of opinion.