Even though Grammy nominations will not be announced until later on Wednesday, organizers of the music industry's top awards have already signaled that some likely contenders will include teen idol Justin Bieber and pop star Katy Perry.

Both are scheduled to perform during a one-hour concert special televised on the U.S. CBS network when nominees will be announced in five major categories.

The event, beginning at 10 p.m. EST (0300 GMT Thursday) in Los Angeles and broadcast live to viewers on the East Coast, also features performances by rock band Train, rapper B.o.B, country singer Miranda Lambert, and singer/songwriter Bruno Mars.

Traditionally, most performers in the program end up with Grammy nominations. Last year's roster included French DJ David Guetta, funk band the Black Eyed Peas, soul singer Maxwell and country group Sugarland. All scored nominations, and all but Sugarland ended up with statuettes.

Industry pundits also expect Eminem to figure highly in the big categories, including album of the year for his latest release, "Recovery," which will likely be the biggest seller of 2010 in the United States.

BIEBER BEST NEW ARTIST?

Grammy voters love to reward artists on the comeback trail, especially if they have overcome an addiction or other personal setbacks along the way, and the 38-year-old rapper fulfills those criteria.

He went almost five years between studio albums, spending much of his time holed up in his Detroit home battling an addiction to prescription medication. He nearly died of a methadone overdose in 2007.

Eminem returned to the limelight in May 2009 with "Relapse," an album that chronicled his personal demons. It was one of the biggest sellers of the year, and picked up two Grammys last January, bringing his career tally to 11.

In quick succession, he returned in June with the companion piece "Recovery," which spawned two chart-topping singles, "Not Afraid" and "Love the Way You Lie." The tunes could vie for record of the year and song of the year. The former award goes to the artist, the latter to the songwriter.

Nominees for album, song and record will be announced during Wednesday's event, along with contenders for best new artist and female country vocal performance.

Pop singer Perry could also figure in the top categories. She enjoyed two of the biggest hits of the year with "California Gurls" and "Teenage Dream," the title track of her new album. But the album itself was a relative sales disappointment.

Bieber, B.o.B and Bruno Mars will likely be among the five nominees for best new artist, a category whose previous winners included future stars like the Beatles and Mariah Carey, as well as where-are-they-now acts like Debby Boone and Starland Vocal Band.

Sade, the British soul singer who fronts the band of the same name, won that award in 1986, and is expected to vie for some top prizes this year, including album of the year for the chart-topping comeback "Soldier of Love."

Another top group, country trio Lady Antebellum, is likely to receive Grammy attention for "Need You Now," the album that ended Sade's three-week reign atop music charts in March.

Last year's big winner, country-pop singer Taylor Swift, will not be a big presence this time around. She released her new album last month, after the Grammys' 13-month eligibility period ended on September 30.

As soon as the TV special ends, Grammy organizers will publish the nominees in more than 100 categories, covering virtually every genre of music from pop, rock, country and hip-hop to Latin, gospel, jazz, polka and classical.

Winners in all categories will be announced during ceremonies scheduled for February 13 at the Staples Center in Los Angeles.