Powerbooks and Variable Timing

PowerPage.org claims that upcoming Powerbook revisions may employ new motherboard technology involving variable timing to extend battery life:

Prototypes have been seen sporting a new "variable timing bus and processor" in which the processor and the bus speed are governed by processing demand, a sort of high/low mode which effectively doubles battery life for such mundane tasks as watching DVDs or listening to music CDs.

This is presumably distinct from the processor cycling advantages that current laptops already perform to increase battery life.

Powerpage continues to maintain a January release of new Powerbooks.