P45, or "Eaglelake" was always scheduled to launch 2Q'08... not been delayed, yet.
As far as X48, was delayed for surplus stock of X38 to push still. In my humble opinion should never of had X48, but I've said that before in other threads.
P31, P35, X38, X48.... G31, G33, G35, G43, G45, and the list continues. Perhaps ya see why I was ranting about it a few months back, now?
Edit: Might even get worse with Nehalem... LGA1366 and LGA1160, two sockets... more excuse for extra chipsets. Or maybe not.