AMD's PR ratings (2800+) means roughly equivalent to a p4 of the same speed. The AMD chips are clocked lower and have a lower FSB due to differences in architecture.
As for looking at benchmarks, this is where you have to be careful, because being the bully that Intel is, they have groups make benchmarks that include more of the p4's strongpoints than the AMD strongpoints. you have to look at a full array of benchmarks and then decifer them for yourself.
AMDs give a much better bang for the buck. But they do need a little more in cooling than the p4s when overclocking.
site plug:
www.amdmb.com