And thats cause its base hardware is alot worse then the Xbox. Xbox GPU, video card, is more then twice as strong as the PS3.
Please... stop spreading false informations!
PS3 has better hardware, it's just a lot harder to develop on it because of the custom architecture. On the other hand, the xbox has the same architecture as a PC so it's easier to develop on it since game are developped on PCs.
But hardware wise, the xbox is the lowest common denominator. (that does not mean that is not a great machine)