Bob Lutz, the charismatic, fiery and egomaniacal automotive genius behind creation and development of the Chevrolet Volt extended range plug-in hybrid, due for sale in 2010, is leaving General Motors, the corporation announced yesterday. Since 2001, the 76-year old Lutz served as GM vice-chairman and product czar, answerable only to company CEO Rick Wagoner.

The announcement came not from Lutz's office, but in a press release from GM corporate, leading many to wonder...