Santa Claus hasn’t appeared on the “Christmas in Rockefeller Center” treelighting special in years. But another magical man who can cover a lot of ground in one night did stop by – Usher.

He was able to help out his pal and trainee Justin Beiber Wednesday as well as stop off later in L.A. at another supposedly live concert event – the Grammy Nominations concert.

While he added a little depth to the seasonal performance of the standard “A Christmas Song,” a lot of the New York audience barely seemed to noticed. They were fixed on the person Brian Williams called “The Beibs” – with most of them intent on capturing it on their phone in a way to prove it was actually happening. (Or maybe they just couldn’t believe his outfit – a weird leather one piece with big brass buttons. It looked like he had been swallowed by a couch).

Usher wasn’t even the biggest name duet partner for Bieber in the special. That came during the premiere of his duet with Mariah Carey on a remake of her “All I Want for Christmas is You.” It was a bit of a comeback for the sultry singer who is six years older than Justin Bieber’s mother. After giving birth to twins she was back at seduction weight and insistent on turning her back to us and hiking her skirt in a very un-Christmasey way, as if she had sat on some mistletoe. But the video itself was so badly done, it reminded you why they had gone so completely out of style.

This is not to say Bieber dominated the special – there was time for Michael Buble to sing two songs (he, too, has a new Christmas album out to sell), Tony Bennet to sing one, and Neil Diamond to growl a carol, “Joy to the World.” Carole King too followed his tradition – a Brill Building Jew singing songs of Christmas.

Big Time Rush did a pop song immediately after Tony Bennett, making them look like his long lost great-nephews. (But they sang a terrible poppish song).

There were NBC shows to sell besides “Nightly News.” First year winner of “The Voice” Javier Colon sat to sing “It’s the Most Wonderful Time of the Year”; Katharine McPhee, who will star in the upcoming “Smash,” got to sing a Christina Aguilera song apropos of nothing (other than its her first single from the show).

That other jolly man of the season, Al Roker, returned to co-host with another impossibly tall co-host, Savannah Guthrie. His funniest moment came when he said “We’re just minutes away from the moment we’ve all been waiting for” and the caption below him said “New ‘Harry’s Law’ Next.”

He was talking about the tree of course and after a deadzone of three minutes or so as a crowd estimated at a half million paused while a music video played, the mayor finally got around to flicking the switch. A choir “Joy to the World” (again) and Guthrie announced the official start of the season.

As pepper spray victims in Walmarts everywhere know, it had started much earlier without them.