Justin Bieber And Mariah Carey Christmas Duet

You knew it was going to happen. When Justin Bieber delivered news of a Christmas album, we immediately began scratching our heads and wondered how it would compare next to the greatest Christmas compilation of all time -- Mariah Carey's, of course. Well, now it's the best of both worlds: the Biebs posted a video on Twitter yesterday that had Mariah cheerfully informing us that she will resurrecting "All I want For Christmas Is You" as a duet with Bieber.

The pint-sized pop star had previously announced a collaboration with Boys II Men on the forthcoming album , to be titled "Under The Mistletoe."

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