If the Athlon XP 3000+ (Barton core) really comes out at 2166 MHz, I think it is hardly able to compete with the Pentium 4 3,06 GHz. This probably is yet AMD's goal, launching a product that is a good alternative for Intel's fastest Pentium 4. The difference in clock speed is a whopping 900 MHz. Even the experienced customer will see that the rating system doesn't make any sense nowadays. Yes, the cache is doubled to 512 KB; however the clock speed has decreased to oldskool levels. We have to pay a huge amount of money for the larger cache size.
If you opt for the best balance between price, performance and sounding clock speed as well, the Pentium 4 (any choice from 2,40 to 2,80 GHz) is the way to go, with the best AMD choice still the Athlon XP 2400+.
I think that if AMD will stay in the race, they have to raise the clock speed to at least 2,40 GHz.