New York City has unveiled new emission standards for its fleet of 10,000 “black taxis” (aka, limos and town cars) that service mostly corporate clients. The plan effectively mandates shifting to hybrid vehicles by 2009 to meet the increased standards of 25 miles per gallon in 2009, and 30 mpg by 2010. The fleet now averages between 12 and 15 mpg. NYC’s new “black taxi” standards are similar to the rule for other taxicabs announced last year that also requires a shift to hybrids by the end of 2009.