I think it does, cos the frequency of the oscillator is higher... (http://en.wikipedia.org/wiki/Clock_rate) Which is why, slower processors also dissipate less heat... while more powerful processors require more cooling. But yes... (wishfully thinking) we would do well to have the iron man thingi on out phones
The Cortex-A9 power-optimized hard macro implementation delivers its peak performance of 4000 DMIPS while consuming less than 250mW per CPU when selected from typical silicon.
The Cortex-A8 processor can meet the requirements for power-optimized mobile devices needing operation in less than 300mW; and performance-optimized consumer applications requiring 2000 DMIPS.