Apple lists the maximum power consumption of a 20" Dual Core iMac at 120 watts, while Tom's tests - even with both 2.0 GHz cores maxed at 100% CPU usage, 1 GB RAM, WiFi, BT, 128 MB graphics card and (oh yea) a 20" LCD - found the iMac drawing a steady 95 watts of power. Assuming that the typical LCD draws around 32 watts of power alone, that means the iMac - even at full throttle - is running as 63 watt personal computer. By comparison, Intel's old Pentium 4 architecture that still ships in many computers needs anywhere from 300-400 watt power supplies - and that's just for the computer itself, sans-display. I should know, I used to build them for a living.
Ultimately, this should boil down to great news for the computing industry. Tom Yager's even so excited about the results that he's issued a friendly challenge to the PC market to find a machine that can claim the same stats. The one question that still bothers me about these new chips, however: why hasn't Apple placed at least an estimated battery life rating on the MacBook Pro?