OK, just to clear stuff out.
The PS3 processor is called 'Cell'. It's not produced by Sony, it will be produced by IBM and Toshiba.
This CPU has been described as being 10 times as powerful as the P4. Also, it has been said the Cell will most likely run above 4GHz.
This is partially true, the Cell will probably run on more than 4GHz, but it's calculating power is about three times less than a P4 3.8GHz.
Apart from that, the Cell is entirely incompatible with x86, which means that if Cell will be introduced for PC's, all software needs to be rewritten.