"there may be data on Intel’s 65 nm parts which would change my buying decision."
Anything is possible I suppose. And if you are going to restrict yourself to 32 bit and Intel announces plans to put Yonah on the desktop, then it could be worth it. Otherwise you are looking at end of 2006 and those intial Conroes aren't going to go into $400 desktops. That will probably be mid-2007.
All assuming Intel can stick to their roadmap, that is.