2010 Prius Delivers Record Mileage and Accelerates Plug-in Plans

DEveloped in 1977, the Toyota Prius today achieves a record 50 miles per gallon --the new 2010 Prius, that is. It just made its formal debut at the North American International Auto Show.Thew good news down the road? Toyota will make a hybrid drive system optional on all vehicles by 2020.