With just three days' notice, Meghan McCain canceled a book tour appearance Thursday at Pennsylvania's Juniata College because of "several unforeseen professional responsibilities," her rep told the college. Busted. The Chronicle of Higher Education looked at McCain's Twitter account and found this: "First real time off in months -- was gonna rest up for phase two next week of my Dirty Sexy Politics book tour," she tweeted Thursday night. "But headed to sin city with my favorite crew of sinners instead ... Viva Las Vegas baby." And McCain kept on tweeting: No apology to the college, just a hissy fit...