The Reg notes that Intel's cut the P4 6xx prices by up to 34%. You can now pick up a Pentium 670 (3.8GHz) for just over $600USD.

"Intel yesterday pruned the prices of its Pentium 4 6xx processor series by up to 34 per cent. The cuts had been expected. The EM64T-enabled single-core CPUs all feature 2MB of L2 cache and support the customary 800MHz frontside bus speed. They are fabbed at 90nm."