I heard that AMD are giving their new chips names which include numbers that are higher than the actual clock speeds. eg, a 1500 Mhz chip will be an "AMD blah-de-blah 1800" Why? Because they say their chips go faster than Intels, at the same clock speed, and the AMD 1500 is capable of outperforming an Intel 1800.
I also heard that in many benchmarks, the Pentium 4 does WORSE than a pentium 3! Of course, in a year or 2 this might not be the case, as programs start to be written specifically for Intel (which is another reason AMD is better, programs aren't even sucking it's dick like they are with Intel!)