If there was any doubt before, there's no doubt now: Justin Bieber is all grown up.
First, with the release of his holiday album Under the Mistletoe, his manager Scooter Braun told Billboard that the 17-year-old Canadian wonderkid had a more mature sound because "vocally, his balls have dropped."
Then there was the paternity allegation heard 'round the world when 20-year-old Californian Mariah Yeater claimed Bieber fathered her child, prompting the singer to take a DNA test to prove her wrong.
And now - well, take a look at Bieber's new video for All I Want for Christmas, which he unwrapped Wednesday night when he performed at the Christmas in Rockefeller Center TV special. In the clip for his duet with Mariah Carey (who, it seems, really hates pants), the diva gyrates against a wall in a revealing Santa costume while Bieber sings enthusiastically in the middle of an abandoned Macy's.
But don't fret - after a series of product placements (why are we suddenly dying for a Nintendo 3DS?) - Carey and the Biebs manage to find each other in the end, snuggling in a sleigh, surrounded by adoring fans laden with gifts, Carey sporting a tiny red dress and tasteful feather boa.
Remember that innocent young kid strumming a guitar and singing his heart out on the streets of Stratford? Neither do we. Justin, we hardly knew ya.