I have a p4p800-e deluxe - great board, extremely stable (intel boards tend to be very stable) - 500mhz oc on stock cooling without playing with the voltages -> whaddya think of that?
I heard that a p4c800-e deluxe is great overclocker as well, it's just based on a newer chipset (i875 on the p4c vs i865 on the p4p).
If you don't wanna buy a pci sound card, then p4p might be better - supports 5.1 surround just to let you know. p4c does too, but right out of the box it only supplies you with 3 jacks, you'll have to buy 3 extra thingys.
p4p has passive cooling, just in case you're into quietness, not sure about the p4c though.
I like my p4p: great overclocker, CANNOT beat the stability, lots of included accessories.
If you're into overclocking, why not the ABIT IC7 Max 3? I heard that was a great 478 ovreclocker (the best actually, or so I heard).
-The Pentium Guy