Not all electric vehicles are created the same--and that's an important point to keep in mind when you read stories about how China's electric-car market is set to overtake that of the U.S. In China, monthly electric-car sales passed those of the U.S. last September, according to data from the Chinese news site Sina Auto. But the country's reported sales of plug-in cars--what China calls New Energy Vehicles--include both conventional cars and what would be deemed in the U.S. low-speed or neighborhood electric vehicles.