I'll wait until next year when Intel and AMD legitimately break the 4ghz barrier, then 6 more months for the 5Ghz barrier.
I wouldn't hold your breath. Intel cancelled their 4GHz P4 and I'd imagine it will take a while for a chip based on the Pentium-M architecture to ratchet up that high.
The MHz/GHz war is running out of steam, that's why all the major chipmakers are turning to dual-core.
