Anybody who still believes that R&B superstars Rihanna and Chris Brown are not a couple after they performed together at Monday night's KDWB Jingle Ball, then maybe you'll buy this, too: It was the best concert of the year.

An annual promotional concert for Top 40 station KDWB (101.3 FM), the nearly sold-out event at St. Paul's Xcel Energy Center was headlined by rap star T.I. but highlighted by Rihanna and Brown's appearance together.

The couple's sweet holding-hands duet of "Umbrella" was pure high drama in the over-mascaraed eyes of the under-dressed teenybopper crowd. If thousands of girls don't make it to high school today, chalk it up to pneumonia caused by their refusal to leave their skimpy T-shirts and leggings at home in lieu of the subzero weather outside. And if Rihanna and Brown still refuse to admit they're a couple today, then they have subzero credibility.

The rest of the annual school-night-out bash was otherwise a predictable, scripted, sculpted affair. Most of the acts performed in prefab wardrobes to prerecorded tracks broken up by prewritten jokes from the DJs.

Here's a report card from the show:

T.I.: The Atlanta rapper only performed for a half-hour but crammed in many of his songs, largely by cutting them down to just snippets. And yet he found time for plenty of stage banter that was almost as predictable as many of his rhymes. Sample talking point: "Is it just me or is cold as a [expletive] out there?" Grade: C+.

Rihanna: For the boys in the crowd, Christmas came early in the form of her Santa-red jacket, knee-high leather boots and the long lines of skin shown in between. For the girls, she also bared ample amounts of empowerment and attitude. And for the non-Top-40 fans, she showed good taste with her snippets of the White Stripes' "Seven Nation Army" and M.I.A.'s "Paper Planes." Everyone ate up her versions of "Take a Bow" and "Don't Stop the Music," which came across clearer and livelier than when she opened for Kanye West over the summer. Grade: B+.

Chris Brown: He did one song himself, "Forever," and then stood by his gal for "Umbrella." Grade: Depends on what he got paid for the gig.

David Archuleta: Like a majority of his fellow "American Idol" alum, this runner-up from the last round of "AI" was strong in voice but light on decent material. The 17-year-old wound up covering Vanessa Carlton's "A Thousand Miles" to help fill the hole. His hit finale, "Crush," showed off his soulful voice but featured a stiff approach. Grade: C.

Boys Like Girls: The emo-pop band was plagued by sound problems. It was still easy to hear its formulaic approach to light, fluffy, girl-baiting rock songs -- which would've been fine if frontman Martin Johnson hadn't tried to toughen it all up with a leather jacket, sunglasses and a bunch of F-bombs. Grade: D+.

Lady Gaga: Really?! The faux New York club princess came across like a bad skit from “Saturday Night Live” of a futuristic pop star, with zero talent, mannequin looks, loads of gimmicky stage poses and incredibly obnoxious get-the-party-started songs. At least “SNL” producers would have the smarts to make her lip-sync, though. Grade: F.

Shontelle: A Barbados native like Rihanna, she started the show on a high note, coming off like a lighter, cutesier Mary J. Blige. Most of the crowd of 13,673 showed up early enough to turn her hit "T-shirt" into a sweet singalong. Grade: B.

Chris Riemenschneider • 612-673-4658