Regardless of all that jargon, I stick to the benchmarks. Numbers can be spat at me all day long, but, in the end, their actual performance is what I care about. I've seen too many benchmarks from both games and number crunching apps to know that AMD is my choice. AMD pretty much kills Intel in gaming and isn't too far behind in other apps. The big cache on the P4s was made so they had an answer to AMDs latest line of chips. They didn't actually have those in their long-term gameplans. While the huge caches do help quite a bit, AMD is still the clear winner when it comes to performance and future upgradability with the 939 socket.
Just for the record, I'm not one of those hardcore AMD fans. I've actually never owned an AMD based computer in my life. It's been Intel up until now. Times are changing though.