Well, in the future the AMD would be a lot better than the Intel P4.
I'd have to say the Intel Pentium 4 3.2Ghz with HT will do fine for a personal computer. The average joe at this point in time doesn't need more; maybe in the future, maybe not. But even so, how long will it take?
I saw an interesting documentary on television, and it said that the average person will never need 64 bit processors. However, those who do graphics design and other things will. It really depends on what you will be using your personal computer for. Just surfing the net, and other simple things, or doing heavy graphical work, making flash files and so on?
I'm actually getting a new computer pretty soon myself, and am going to get an Intel Pentium 4 (Only 3Ghz with HT mind you), as I don't feel that I need a 64 bit computer at this moment in time. Will I ever? Maybe, as I do do quite a bit of graphical work, however if I find in the future I need one, then I will buy another computer as by then, as Gordy said, they'll most likely have something better on the market - and what's available today will be cheaper.