AMAs '10: Best/Worst Performances

RIHANNA
The pop queen perched demurely on a branch of a fiberglass tree as the show opened, singing the first verse of ''Love the Way You Lie (Part Two).'' It's a somber ballad, maybe an odd choice to kick off the night's festivities — but soon enough, Rihanna hopped down and launched seamlessly into her wildly catchy hit ''What's My Name,'' followed by a spirited rendition of the similarly up-tempo ''Only Girl (In the World).'' Nicely saved. Grade: B+

ENRIQUE IGLESIAS
How could Iglesias perform his new single ''Tonight,'' whose chorus is built around the elegant couplet ''I don't mean to be rude/But tonight I'm f---ing you''? Easy: Just change the operative word to ''loving.'' Ah, modern romance. Afterward, Pitbull (pictured, left, with Iglesias) and a drumline marched out for Jersey Shore favorite ''I Like It.'' Auto-Tuned fun was had by all. Grade: B

MILEY CYRUS
Candelabras dripping crimson wax, long black dress sweeping the floor, mopey midtempo guitars — tonight only, Miley goes goth! Her vocals on ''Forgiveness and Love'' weren't quite up to the task, but give her points for atmosphere. Grade: C+

DIDDY-DIRTY MONEY
The rap mogul is giving his little-heard singing voice more mic time on his long-promised new album Last Train to Paris. Crooning sad-sack ballad ''Coming Home'' with his backing group Dirty Money, he actually kind of pulled it off. One question, though: How can he say ''I hate that song'' of Smokey Robinson and the Miracles' ''The Tears of a Clown''? C'mon, Diddy, that song is a stone-cold classic! Grade: B-

KID ROCK
Rugged rock 'n' roll soul à la Bob Seger is what the Kid is aiming for on his latest album, Born Free. Singing an acoustic take on ''Times Like These,'' his tribute to Detroit, he just sounded uncomfortably hoarse. Throat lozenge, anyone? Grade: C

BLACK EYED PEAS
Performances by the Peas are as much about visual spectacle as actual songs. Tonight, riding stage elevators and dancing with funky robots in front of a frenetic video wall, they looked very cool. Their current single ''The Time (Dirty Bit)'' isn't their most memorable, but who really cares? Grade: B

KATY PERRY
''Firework'' benefited from some impressive stagecraft as well. A bowtie-bedecked children's choir began the song before Perry descended dramatically from the ceiling to cavort with dancers brandishing pyrotechnic flares. The only part of the package that could have used some work was Perry's occasionally sour vocals. Grade: C+

JUSTIN BIEBER
The teen phenomenon is currently promoting an acoustic album, so naturally he began performing his heavy-hearted single ''Pray'' as a spare piano ballad — a risky choice for such a thin-voiced singer. Soon a gospel choir joined him on stage, helpfully covering some of the notes he was having trouble reaching. Grade: B-

BON JOVI
The rockers raised the average age of tonight's performers when they took the stage for ''What Do You Got?'', one of the new songs included on their recent Greatest Hits. They made a much stronger case for that retrospective set by segueing into a time-tested medley of ''You Give Love a Bad Name'' and ''It's My Life.'' Grade: B

PINK
The star just announced that she's expecting a child. Thankfully, that didn't stop her from giving one of the night's most energetic performances with ''Raise Your Glass,'' complete with stage kicks and awesome air-guitar licks. Grade: B

NE-YO
In between brief videos outlining the concept of his new album Libra Scale — it's about superpowered sanitation workers in love — the smooth singer-songwriter ran through parts of his tunes ''Champagne Life,'' ''One in a Million,'' ''Telekinesis,'' and ''Beautiful Monster.'' His falsetto was one of the show's finest live voices by far. Grade: B+

TAYLOR SWIFT
She's been known to struggle with awards show performances in the past, but Swift nailed this one. Her voice sounded stronger than ever on ''Back to December,'' an eloquently regretful highlight in tonight's show. Grade: A-

CHRISTINA AGUILERA
Her striptease-themed performance of the Burlesque soundtrack tune ''Express'' had plenty of racy choreography and bared skin, but the song was just okay. Still, Aguilera proved a powerful vocalist as always. Grade: B-

USHER
A decade-and-a-half after becoming a pop star, Usher still routinely pulls off slick dance moves that put his younger peers to shame. His actual singing on ''DJ Got Us Falling in Love'' (over banging beats from Swedish House Mafia) was slightly underwhelming, but that's just nitpicking. Grade: B+

TRAIN
The resurgent pop-rockers swung from an understated ''Marry Me'' to a happy-go-lucky ''Hey, Soul Sister.'' On the latter number, they were assisted by dozens of female dancers in t-shirts reading ''SOUL SISTER,'' an amusingly literal staging choice. Grade: B

KE$HA
Her performance of ''We R Who We R'' seemed to feature as much cheesy vocal processing and special-effects glitter as the rest of the awards show combined. At one point, she pretended to strum a huge guitar, only to smash it awkwardly on the ground. Over-the-top gestures are well and good, but that's about all Ke$ha had to offer. Grade: C-

SANTANA
Guest singer Gavin Rossdale helped guitar god Carlos Santana tear through a grungy version of T. Rex's 1971 hit ''Bang a Gong (Get It On).'' The old-school vibes were a touch unexpected at the very of-the-moment AMAs, but in a welcome way. Grade: B

NEW KIDS ON THE BLOCK/BACKSTREET BOYS
Worlds collided as the two acts took the stage together to form a nine-headed hydra of boy band charisma. The mashed-up performance that followed, including bits of ''Hangin' Tough,'' ''Everybody,'' ''I Want It That Way,'' ''Step By Step,'' ''The Right Stuff,'' and ''Larger than Life,'' just might have convinced some doubters to buy tickets for their joint NKOTBSB tour. Grade: B+