yeah...Core 2 Duos are. I built my C2D system last week. Installed XP 64-bit and then i just ended up taking it off and puttin gon the regular 32-bit version because i couldn't get the stuff to work that well.
my vote is to wait for vista's 64-bit technology cuz IMO XP Pro 64-bit sucks and isn't even worth putting on for free (mine came bundled w/ pro for $5 and i don't use it.)
adn BTW my conroe stock is slighltly slower than a FX-62 and w/ a good mobo it was only $400 (US) total. So...no Intel's 64-bit chips are not expensive, at least for what you get.
Antec NeoPower 650W
Intel Core 2 Duo E8400 (w/ Arctic Freezer 7)
4GB DDR2-1000 G.Skill
Sapphire x1950 Pro 512mb (w/ V700)
250GB, 500GB and 1.5TB Seagate Barracudas (2.25TB total)
Fatal1ty XtremeGamer sound card *** generic TV tuner
Xclio 3060 case *** HannsG 22" monitor
XP Pro / Ubuntu 7.10 *** Razer Copperhead and Tarantula