Latest Media Attack on Palin: She Flew on Jet

It was billed as a bus tour, but Sarah Palin's travels across the country to promote her new book have included several flights on an expensive private jet, her publisher told ABC News.

The former Republican vice presidential candidate and Alaska governor, who sold off a private jet belonging to the state calling it "over the top," has been getting around the United States to promote her book aboard a Gulfstream 2 private jet -- at a cost of $4,000 per hour.

It's not unusual for politicians to regularly take planes on tours and then board a campaign bus to arrive at a stop, but in an era in which private jets carry a special sort of stigma, Palin may be vulnerable to criticism.