Maybe I missed it somewhere in this long thread, but lower emissions and higher economy is achieved partly with the use of the Atkinson Cycling of the ICE. The Atkinson Cycle sacrifices some serious Torque, but the combo with Electric drive motors replaces the low end Torque loss.

Combine this with some serious program control of the entire power train, and you have the beauty of the Hybrid. Many wonder why elements of this have not been applied to all vehicles? Any one of these as a standalone solution would turn the average eco cruiser into a real dog, but in combo together you get decent performance, and a heck of a reduction in emissions.

I also noticed little mention of the impact Auto-Stop has on emissions control. This makes a huge contribution to lowering emissions. Even the GM approach with a Belt Alternator Starter(BAS) system will have dramatic impact on emissions, while providing little mpg relief.

Serious engineering and finances have gone into these platforms, and I guarantee none of the manufacturers are taking this lightly. Even if all vehicles featured Auto-Stop, the environment would be dramatically impacted for the better. Gas powered Golf Carts have had Auto-Stop for a decade, although very crude.

I think within the next ten (10) years we can go back to picking our cars against all the old scorecards without melting the polar ice caps in the process.

It's all good!