As if the thousands of other reasons weren't enough, there's this:
Gingrich responded that Palin “is certainly one of the people you would look at” [for vice president] and told the caller that he is “a great admirer of hers.” He also floated the idea of appointing her Secretary of Energy because, he said, “I can’t imagine anybody who would do a better job of driving us to an energy solution than Gov. Palin.”
To even float such an idea is completely insane. Our current Secretary of Energy, Steven Chu, is a Stanford physicist and a genius. Sarah Palin can, um, speak without swallowing her own tongue. Barely.