Honda has a clone coming out too. What is sad is Ford and GM (Opel) have modern direct injection diesels in Europe that get better mileage than the current and new and improved Prius.
The Dems are blocking importation of them. These new diesels are cleaner, quieter and fast. BMW, Audi, Mercedes, Puegeot, Renault, Honda, Fiat also have euro diesels.
Ford has a diesel Focus that gets about 55 mpg. It was just named the Greenest Family Car in the UK.
http://www.telegraph.co.uk/motoring/3202438/Ford-Focus-named-greenest-family-car.html
New Ford Fiesta gets 65 mpg
http://www.businessweek.com/magazine/content/08_37/b4099060491065.htm?chan=autos_autos+—+lifestyle+subindex+page_top+stories
A diesel Fiesta probably could get 75 mpg.
We can make diesel engines meet American emission control standards, but the emission control systems are complex and very costly--so much so that you'll be better off with a Toyota Prius or Honda's new Insight family car due next spring.