Intel may start moving to a 45nm process sooner than expected after issues with that technology were overcome. Seemingly, the leakage problem experienced with that technology has been solved, and soon we might be seeing the first 45nm product, perhaps a shrink of the 65nm Merom product, and possibly called Penryn.
Going to 45nm will GREATLY reduce power consumption compared to the 65nm parts that are soon to be released, and extremely compared to existing 90nm products. A very simplistic estimate would be that power consumption will drop by a factor of four (square of the difference of feature size) compared to the 90nm process, so a Prescott re-done in 45nm might only generate 25W-30W of heat. Now a Pentium-M derived core would obviously generate even less heat - dare we hope for 5W or less?