I've been flying home for Christmas since 2001. I always leave sometime around December 21 or 22, and I have never had a problem. I've flown through cities like Denver and Chicago and things have always gone miraculously smoothly. Last year, Kevin and I flew here separately and neither of us hit any snags. So leave it to the one year that both of us fly here together for everything to go haywire. Thanks to me booking a flight that passed through Chicago, and to United for having "mechanical" problems that prevented our flight from leaving on time, today I got stranded in Chicago when United "postponed" our flight for twelve hours, and am having to spend the night in the lovely O'Hare Airport Westin. I'd never throw a party here, but for free* airport accommodations, it's actually pretty lovely.
*Free only before paying $10 to connect to the internet so I could see if we actually do have a flight tomorrow, and before paying $50 for dinner, which United decided not to pay for.