MC Hammer and singer PSY perform onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

(L-R) MC Hammer and singer PSY perform onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Christina Aguilera performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Christina Aguilera performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Justin Bieber accepts the award for Favorite Pop/Rock Album from Jenny McCarthy onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Presenter will.i.am speaks onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer PSY performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Rapper MC Hammer performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Presenters Gavin DeGraw and Colbie Caillat speak onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singers Nicki Minaj (L) and Justin Bieber perform onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Chris Brown performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Presenters Curtis "50 cent" Jackson and Hayden Panettiere speak onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Carrie Underwood accepts the award for Favorite Country Music Album onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Recording artist Nicki Minaj accepts the award for Favorite Rap/Hip-Hop Artist onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Recording artist Pitbull performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Chris Brown (L) and rapper Ludacris perform onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Justin Bieber accepts the award for Favorite Pop/Rock Album onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Justin Bieber (R) accepts the award for Artist of the Year with Pattie Malette onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

(L-R) Presenters Charles Kelley, Hillary Scott and Dave Haywood of Lady Antebellum speak onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Christina Aguilera performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer PSY performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Taylor Swift performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

(L-R) Presenters Lucy Hale and Phillip Phillips speak onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Rapper/singer Nicki Minaj performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Kesha performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Gwen Stefani of No Doubt performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Presenters Amy Heidemann and Nick Noonan of Karmin of speak onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Pink performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Chris Brown performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Justin Bieber performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Kesha performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Carly Rae Jepsen accepts the award for Old Navy New Artist of the Year onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

(L-R) Musicians Tom Dumont and Tony Kanal perform onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Presenter Heidi Klum speaks onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singers Nicki Minaj (L) and Justin Bieber perform onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

(L-R) Presenters Nick Carter, Howie Dorough, Brian Littrell, Kevin Richardson and AJ McLean of Backstreet Boys speak onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Rapper Ludacris performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Taylor Swift performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

(L-R) MC Hammer and singer PSY perform onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Gwen Stefani of No Doubt performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Usher accepts the award for Favorite Soul/R&B Male Artist onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Kesha performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

Singer Carly Rae Jepsen performs onstage during the 40th American Music Awards held at Nokia Theatre L.A. Live on November 18, 2012 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)