This article, although rather technical (or perhaps because of it) seems to paint a dark and ominous cloud on the horizon for nVidia.
It looks increasingly likely that AMD will be in a one Horse race with it's 5 series cards having no real competition. They have already come to market well ahead of nVidia, and when nVidia finally do launch, it seems likely the cards are going to be very dissapointing, on pretty much every aspect of their hardware design (performance; power consumption; heat; size) not to mention price
I should mention I've owned mostly nVidia cards, but am currently running an HD5770 in my gaming rig and have been blown away by the performance it offers, at such a reasonable price and low power consumption. Furthermore, this card is ideal for a crossfire setup (again due to it's low power; size and price). Reviews have shown in crossfire it scales amazingly well.
Maybe still a bit too early to make the call, but I think this round is going to belong to AMD in a very big way