It's hard to really take benchmarks seriously. AMDs, since K6 days, have always had an upper hand in many popular benchmarks. Windows might even boot faster and open small programs quicker. However, in my experience, the increased memory throughput of the Pentium 4 vs Athlon XP makes a significant difference in running current software now and that Pentium 4 systems generally could take more of a load before starting to slug out. Of course, SSE helps as well.
Though I suppose with radically different designs, both chips would have their own advantages which cater to different users who do different tasks with their PCs. That's probably part of why the argument as to which is better will never end.
EDIT: In retrospect, one must imagine if AMD never succeeded with the Athlon and K6 cpus. Intel was forced to acknowledge AMD had some competitive products and thus, we had a pretty healthy technology race. At the same time, one must also imagine if there never was much competition. Would the chip makers simply take advantage by continuing lesser designs or would they take advantage of having more time to refine each new product. After all, on both sides, there were a couple of dud products pushed out simply for the sake of buying time. Also, most notably in Intel's case, a good design (NetBurst) was pretty bastardized with long pipelines and premature designs being released in the name of having the fastest cpu on market.