Mariah Carey BMI Awards Tribute: Marsha Ambrosius, Eric Benet & Joe Praise Singer

Though Mariah Carey arrived late, many of hip-hop and R&B's biggest stars gathered at the 2012 BMI Urban Music Awards in Beverly Hills, Calif., on Friday (Sept. 7) to celebrate the 42-year-old singer, who was presented with the performance rights organization's Icon Award.

The event, which featured surprise performances by Nas and Future, was hosted by BMI President Del Bryant, VP Catherine Brewton and Ray J. Attendees included everyone from Randy Jackson and Jermaine Dupri to Birdman, Mac Miller and Big Sean.

The star of the evening, however, was Carey, who was honored for her songwriting achievements, and referred to as "the greatest singer in history" by the BMI chief.

"I consider her a national treasure. She's got one of those rare, once-in-a-lifetime Whitney, Aretha, just amazing, unique talents," Eric Benet told The BoomBox, before serenading Carey with her song "One Sweet Day" during a tribute which also featured contributions from Dupri, Fantasia and Joe.

"I think it's gonna be something that should happen every year because she's given so much to the industry," Joe told us of the celebration. "I have that much respect for her because she reached out to me -- a young R&B singer who really needed that support from a major icon like herself. I appreciate her on that behalf, so I'm definitely celebrating her life tonight."

Also on hand for the event was singer Marsha Ambrosius, who praised Carey for her talents as well as her longevity.

"She's managed to be everything every decade. Everything," she exclaimed. "To do that is honorable."

Following the tribute, Carey took the stage to accept her award, appearing deeply moved.

"I'm sweating and crying ... I don't know which way I'm going. But I'm happy to be here," she said. "I can't thank you enough for doing something beautiful with the songs I wrote. I'm so humbled by this moment. A lot of people still don't know I write my music. Singing material so close to my heart tonight ... it has helped change my life."

Several other artists received awards for their songwriting, including Nicki Minaj for Song of the Year ("Super Bass"), Lil Wayne and Drake for Songwriters of the Year (Drake's second year in a row), and Mac Miller, who took home BMI's first-ever Social Star Award.