The Folding@Home staff accidentally confirmed the ATI RV770 will have 480 shader processors. The original post has already been edited but it said this:
We've been very much keeping the new hardware in mind. Note that the high end board has 480 SP's (960 is for the X2, which means that we could hopefully run 2 copies of FAH on that once everything gets worked out). We've already been keeping in mind the larger 480 SP count and there are larger WU's on the way which are going to be very exciting from the science point of view and should use all 480 SP's nicely (we hope -- we're still testing).