No one in the world has a justified knowledge of the fact that the 360 is more powerful.
We do not yet know what the PS3, and even the 360 can do.
It has been about 2 years for devs on the PS3, we won't know which is more powerful for a long time.
We do know which one has the setup of a PC though, making it the easiest to dev for, which creates flame threads like this in the first place.