Citing an anonymous tipster from inside the search firm Spencer Stuart, Silicon Valley Insider notes that Cook is the "...top candidate that Spencer Stuart has identified as the next CEO of GM." With Microsoft CFO Chris Liddell recently announcing that he will be GM's next CFO and vice-chairman, Cook would become the second "gadget geek" to take a significant role at GM.
Considering the less-than-inspiring designs that Chevy, Buick and the now-defunct Saturn have been producing, as well as his performance while interim CEO of Apple (known for world-class design), Cook is a logical choice. But would he want the job? Most believe that he's sure to take over for Steve Jobs for good once the time comes, plus he picked up a cool $12 mil. while standing in for Steve this year. That will build a little loyalty.
For now, this is all speculation. We'll keep an eye on this story as it develops.