After years of criticism from greens and independent testing groups, the U.S. EPA announced on Friday that its rules for testing automobile fuel economy will finally be updated and revised. New standards should be in place for testing 2008 model year cars. It’s a move long opposed by the automobile industry, since the revisions could decrease mile-per-gallon estimates for new vehicles by as much as 10 percent.

Most environmentalists agree that boosting fuel efficiency in cars is the number one challenge in the battle to scale back both America's greenhouse emissions and our dependence on foreign oil. So it's excellent news that states are stepping up to impose stricter fuel-efficiency standards—particularly at a time when federal leaders in Washington are shrinking away from the issue. Vermont has decided to follow California's lead and require that all new cars and trucks in 2012 emit 22 percent less carbon dioxide than today’s vehicles.