Rapper Eminem and pop star Justin Bieber ruled the 2011's Billboard Music Awards on May 22, tying for the top spot, each winning six awards.
Second place was also shared between Lady Gaga, Rihanna, Mumford & Sons, Usher, Taylor Swift and Taio Cruz, who each won three awards.
Ken Jeong of The Hangover films hosted the live event at the MGM Grand in Las Vegas.
Performance highlights included a duet of "S&M" from Rihanna and Britney Spears, and Cee Lo Green sang a medley of hits, from "Crazy" to "Forget You," upside down and playing a piano which levitated 12 feet above the stage and twirled around 360-degrees.
A special Millennium Award went to Beyoncé with an illustrious tribute by America's First Lady Michelle Obama, legendary singer Barbra Streisand, Lady Gaga, Stevie Wonder, and more.
Also, special awards went to U2 for the Touring trophy, Neil Diamond was honored with an Icon Award, and Cee Lo received the Viral Innovator Award.
Eminem took Top Artist, Top Male Artist, Top Rap Artist, Top Rap Song, Top Rap Album, and Top Billboard 200 Album. His awards were not presented during the ceremony.
Bieber, the Fan Favorite winner, also took Top New Artist, Top Social Artist, Top Streaming Artist, Top Streaming Song, Top Digital Media Artist and Top Pop Album.
Katy Perry, Shakira, Chris Tomlin and Train each won two awards. Receiving one Billboard prize were Bruno Mars, Black Eyed Peas and Will.I.Am, Ludacris, Nelly, Lady Antebellum, Enrique Iglesias, Romanians Edward Maya & Vika Jigulina, and U2.
The telecast also featured performances by the Black Eyed Peas, Keith Urban, Taio Cruz, Nicki Minaj, Ke$ha, Pitbull, and Mary J. Blige with Lil Wayne.
The Billboard Music Awards' winners in 46 categories were determined by a combination of charts and social and streaming activity from February 28, 2010 through March 1, 2011.