I think NT/dual processor/dual core clients are in the work. the problem is that they will have to modify all the folding cores, so i wouldn't hold your breath. As for PPD/PPW, With a single QMD, that presscott could probably get up to 500PPD with tight memory and a little overclock. I'm not sure about the 2GHz, is that the williamette core? probably 100-200 ppd, but that's a big guess.
On QMDs, doing nothing but folding you should expect 270 ppd out of the P4 2.0 and about 590 ppd out of the prescot @ 3.8, assuming tight ram timings and 550 on loose timings. You must report >504 MB of available ram to the assignment server and have -advmethods and bigpackets turned on. Just run one instance on the prescot.