If you're reading this on Monday, and the Bonnie Hunt Show has already aired in your area, fret not. They had the video of Kris Allen's performance of "The Christmas Song" posted on their website - BonnieHunt.com - around midnight Pacific time. (That last falsetto note is to die for!)
And if you haven't yet missed it on your TV, check your local listings for airtimes. In LA, it's on at 3 pm on NBC.
Also doing the talk-show thing on Monday are David Archuleta on CBS' Early Show (7-9 am) and Adam Lambert on The Tonight Show with Conan O'Brien (11:35 pm, NBC)