Grammy Awards preview: What to expect on Sunday

(CBS/AP) The Grammy Awards will be jam-packed with performances this weekend. The ceremony, which airs live on CBS Sunday night, will find Adele - one of the key nominees with six nods - performing for the first time since having surgery on her vocal chords.

There's some other excitement and drama set around the Grammys this year. A group of musicians upset that the Recording Academy has cut the number of awards have vowed to protest outside the Staples Center, where the ceremony will be held.

Chris Brown and Rihanna will perform on the same stage - although at different times - for the first time since Brown attacked her before the 2009 Grammys, forcing both to drop out the show.

And the remaining Beach Boys will reunite onstage for the first time in years.

Kanye West is the top nominee with seven, including a best song nomination for his "All of the Lights." But his highly acclaimed "My Beautiful Dark Twisted Fantasy" and "Watch The Throne," his collaboration with Jay-Z, are not among the nominees for best album, nor is he up for record of the year.

Adele is nominated in all top categories. "21," the year's best-selling album, is up for album of the year, and her "Rolling in the Deep" is up for song and record of the year. Bruno Mars is also up for best album for "Doo-Wops & Hooligans," and his "Grenade" is a contender for record and song of the year as well; he too has six nominations, along with the Foo Fighters, whose "Wasting Light" is up for album of the year.

Other album of the year candidates are Lady Gaga's "Born This Way" and Rihanna's "Loud"; for record of the year, Bon Iver's "Holocene" is in the mix with Mumford & Sons "The Cave" and Katy Perry's "Firework." For song of the year, all the same nominees appear except "All of the Lights" replaces "Firework."

Adele's performance promises to be among the night's highlights. She had to cancel her tour and undergo surgery after persistent throat problems, and has kept a low-profile for months.

Other key performances are to include the Grammy's first-ever dance-electronic music segment featuring the Foos, David Guetta and others, and Bruce Springsteen and Paul McCartney are to take the stage. Taylor Swift, Nicki Minaj and Coldplay also are set to perform.

Another key moment will be the reunion of the Beach Boys, who are scheduled to go on a tour this year. The group was set to announce their reunion at the Grammy nominations special last fall, but Portnow said "the timing just didn't work."

LL Cool J will host the Grammy telecast, which lasts three and a half hours. About 10 awards are given out; the bulk of them are doled out during a pre-telecast. This year, the total number of Grammys was cut from 109 to 78 after a major overhaul last year. Some specific categories were deleted and put in new, broader categories, to the outrage of some who have said the move disenfranchised them.

Watch stars get ready for the Grammys below: