The lunacy of federal tax credits is that the $7,500 credit disappears once a manufacturer has sold 200,000 eligible plug-in electric vehicles. Years ago, for hybrids, it was only 60,000 and that's why there is no more federal money for buying a Toyoa Prius or Ford Fusion or Escape hybrids, but there are credits on the recently-introduced Prius plug-in and Ford C Max Energi.
The California bill (Assembly Bill 1077), by Assemblyman Al Muratuschi of Hermosa Beach, would use existing incentives to lower the cost of all alternative fuel vehicle purchases by reducing state sales taxes. The bill would reduce the sales tax due on an alt-fuel vehicle to what would be required of a "comparable conventional fuel vehicle, as determined by the State Energy Resources Conservation and Development Commission." The bill is supported by EV advocates, including California utilities, automakers like (surprise) Nissan and General Motors and environmental groups.