The EPA has an annoying habit of doing tests on plug in hybrids with fully charged batteries and the test is usually completed on electric alone. Which does not demonstrate the true fuel economy of a car.
I am kinda opposed to the plug in hybrid anyway, as the government is making moves to ban incandescent bulbs for energy savings however we're all going to come home and plug our cars in? Doesn't make so much sense. Our electric is still supplied primary by carbons, whether it is petroleum or coal. Yes, we can offset this by use of solar panels, the wind (and please don't get me started on how bad hydro power is). But simply put the systems need to be in place before the cars make it to the market, on top of that the systems need to be affordable enough and flexible enough to be used in most homes. Which includes the need for the electric companies to get on top of purchasing power from homeowners.. something which is quite popular out in California but not seen widespread across the country. During the day these solar panels are just going to be sitting on the roof of our homes doing nothing, and at night when we come home they won't be of much use. The use of more batteries to offset this is even less environmentally sound. The only thing which makes sense is to do a trade with the electric companies.. they use your power during the day, and you get it back at night when you need it..
There is some talk of the same on the Smart ForTwo platform, seeing milage above 99MPG on the EPA 2008 rating scale. I can't wait 