Credit: Island Records, Columbia Records Photo: Justin Bieber and Mariah Carey Team Up for a Duet to "All I Want for Christmas Is You"

It's a month before Thanksgiving and we're already in the holiday spirit over here at Wetpaint Entertainment, thanks to Mariah Carey and Justin Bieber's duet to "All I Want for Christmas Is You," which just hit YouTube a few days before its official release on Justin's holiday album Under the Mistletoe.

When you really think about it, this "festive collabo" is a pretty ingenious idea — two of the biggest names in music coming together to cover the most downloaded holiday song of all time. An instant hit, right?

We'll let you be the judge.