All of the reviews on the hardware sites indicate that the actual power
usage is much lower than 65W. Here is the Xbit article, they were seeing
33.4W at full load on an 8500, 3.4W at idle. The E6850 was 51.7 at full.
Intel is giving themselves a lot of breathing space with the 65W spec, it
will allow them to introduce a 4GHz part within the same power envelope
if they want. (Take XBit's 34W number, add 40% to account for worst case
conditions, and then add 33% on top of that to account for a 4GHz clock
and you have 63W). The review sites plus a number of people on Newegg
have been reporting pushing the 8400 to 4GHz without to much trouble
which means that Intel could easily create a 4GHz bin if they wanted to.