Will you idiots quit wasting our time and actually answer some questions! (directed to Necromancer...)
To CarpeNoctem, from what I can see, the P4 is the fastest... A centrino 1.6 is about at a mobile P4/2.3GHz, or so.
I don't know too much about Intel's processors(AMD guy myself) but I assume the centrino is more for mobile apps. It's got built in wifi, right? It probably had more power saving features too, and probably runs cooler...