They join previously announced performers and nominees Arcade Fire, Eminem, Cee Lo Green, Lady Gaga, Miranda Lambert, and Katy Perry.

The event will take place live on Sunday, Feb. 13, 2011, at Staples Center in Los Angeles and will be broadcast in high definition and 5.1 surround sound on the CBS Television Network from 8 – 11:30 p.m. (ET/PT).

The show also will be supported on radio worldwide via Westwood One, and covered online at GRAMMY.com and CBS.com, and on YouTube at www.youtube.com/thegrammys. Additional performers, presenters and special segments will be announced soon.

Arcade Fire, Bieber, B.o.B, Lambert, Mars, Monae, Muse, and Smith will perform on the GRAMMY telecast for the first time, while Eminem, Cee Lo Green, Lady Antebellum, Lady Gaga, Katy Perry, and Usher are returning to the GRAMMY stage. All five Album Of The Year nominees are now set to perform on Music's Biggest Night: Arcade Fire, Eminem, Lady Antebellum, Lady Gaga, and Perry.

Continuing in the tradition of creating great "GRAMMY Moments," this year's show will feature a number of special performances exclusive to the GRAMMY telecast with one-time-only groupings of artists. Among this year's unique collaborations, mentor and five-time GRAMMY winner Usher will appear with his protege Bieber, along with Smith, in a dynamic, energetic performance. And B.o.B, Mars, and Monae — whose respective eclectic artistry and universal appeal is reflected in their collective 14 GRAMMY nominations this year — will perform together for the first time in a rare, never-before-seen presentation.

Bruno Mars has seven nominations: two for Record Of The Year for "Nothin' On You" (with B.o.B, Philip Lawrence, Ari Levine and Mike Wilson) and "F*** You" (with Cee Lo Green, Philip Lawrence, Ari Levine, Manny Marroquin and Graham Marsh); Song Of The Year for "F*** You" (with Brody Brown, Cee Lo Green, Philip Lawrence, and Ari Levine); Best Male Pop Vocal Performance for "Just The Way You Are"; Best Rap/Sung Collaboration and Best Rap Song for "Nothin' On You" (the former with B.o.B, and the latter with B.o.B, Philip Lawrence, and Ari Levine); and Producer Of The Year (as a member of the Smeezingtons, along with Philip Lawrence and Ari Levine).

GRAMMY-winning group Lady Antebellum has six nods: Album Of The Year and Best Country Album for Need You Now; and Record Of The Year, Song Of The Year, Best Country Performance By A Duo Or Group With Vocals, and Best Country Song for "Need You Now."

B.o.B is up for five awards: Record Of The Year, Best Rap/Sung Collaboration, and Best Rap Song for "Nothin' On You" (the first with Philip Lawrence, Ari Levine, Bruno Mars, and Mike Wilson, the second with Bruno Mars, and the third with Philip Lawrence, Ari Levine, and Bruno Mars); Best Pop Collaboration With Vocals for "Airplanes, Part II" (with Eminem & Hayley Williams); and Best Rap Album for The Adventures Of Bobby Ray.