Watch Mariah Carey, Justin Bieber 'Christmas' video

The "Superfestive" video version of "All I Want for Christmas Is You" features Mariah Carey and Justin Bieber enjoying product placement, er, holiday shopping. They dance in a Macy's (which they both rep, natch) and Biebs enjoys a Nintendo DS 3D! It gets better when they play with the cute puppy. That said, if you just listen to the song, it's impossible to remain a humbug.