Milo, at best, a change in paste will give you 1 to 3 degrees improvement. Now if they go to a system like Prescott is using, I'm not sure what its efficiency is. I remember reading of a prototype system recently that actually "solders" the surfaces together with a flash heating process. This could possibly give a thermal interface that would be a whole order more efficient that thermal paste. You might ask Mani on SI about it, since that is sort of his area of expertise. I'll try to look around and find what I read.
Any of you Intel enthusiasts know what system they're using on Prescott?
Paul