That's speculation at best, we don't even have proper technical specifications yet.
http://arstechnica.com/gaming/news/2011/01/ngp.ars That said, games made for the PS3
will not run on the NGP. Sony and the developers they had speaking at the conference made it clear that the NGP is
close to the power of the PS3 (similar to how the PSP was close to the power of the PS2, despite being somewhat less capable and requiring a bit of dev work to port titles over as a result), and that they want it to be possible for developers to easily port their titles cross-platform from the PS3 to the NGP, but you won't be playing most PS3 games unless their developers actually bother to port them.