The P4 is doing what it was always supposed to do. Be the basis for the next generation of CPUs. People often forget that the core of the PIII, PII, and Celreon was the old Ppro core. Advanced, and retuned, but still a chip that debutted at 150Mhz. They got that jalopy over a Gig. If they can pull off the same with the P4 core, and I think they can, it has the potential to top 7Ghz.
As for the Hz race, that's nothing more than a marketing tool now. It's meaningless. Right now, AMD does more per tick, but the tendancy now is to serial connections. AMD is still using a parallel philosophy. Intel has set up a technology that lets them do more total. "Specially in a tuned system, using the fastest ram going. A system with bottlenecks favours the AMD, for now.