First Rick Wagoner, now Fritz Henderson. The heads continue to roll over at General Motors, as a second chief executive is stepping down in less than a year. Wagoner was pressured to resign after the government bailed out the troubled automaker earlier this year. The decision was announced Tuesday following a board meeting. GM Chairman Ed Whitacre will serve as interim chief executive while the company searches for a new president and CEO. The move is intended as a way to fast track the company on the road to profitability and repaying taxpayers the $50 billion the government loaned it to recover. It is rumored that Whitacre, a former AT&T exec, and Henderson didn't get along.