"Compared to the Intel® Pentium® III processor, Intel® NetBurst micro-architecture doubles the pipeline depth to 20 stages. This significantly increases the Intel® Pentium® 4 processor's performance and frequency capability."
"Frequency capability" - read as "we can increase the MHz insanely without actually having to make the chip any faster". It's a fact that a 400MHz G3 beats out a 1400MHz P4 in almost every task so far . . . although this is partially true because nobody's written P4-optimized software or compilers yet. It remains to be seen just how good the P4 is once compilers can handle it well.
Ah, marketing . . . would you rather have a 1400MHz P4 or a 1000MHz Athlon? Well, just the context of the question should tell you - the Athlon's better :) And cheaper. Ain't marketing grand . . .