For the second year in a row, the U.S. Environmental Protection Agency has named the Insight as the most fuel efficiency car on the market. However, the highway mileage estimates for the Insight has been downgraded from 70 mpg to 68 mpg. We don't know whether this is due to a change in testing proceedure, or for some other reason. The EPA's city mileage estimated is 61 mpg.

For the first time the Prius is included in the EPA's fuel efficiency estimates. Note that the article listed below on Yahoo incorrectly reverses the numbers. In fact, the Prius achieves 52 mpg in the city and 45 mpg on the highway, not the other way around.

Speaking about the Insight and Prius, the article says "Both cars use electric motors powered by advanced batteries and gasoline engines to vastly improve fuel economy over traditional gasoline or diesel engines." An EPA spokesperson is also quoted as saying "Choosing the most fuel-efficient vehicle in a class can save the owner at least $1,500 in fuel costs, avoids tons of pollution that causes global warming and help reduce dependence on imported oil"

See also:

Article on Yahoo News
Actual lifetime average mileage seen by Insight Owners