REUTERSAnn Hudson and granddaughter, singer Katy Perry, arrive at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSSinger Katy Perry arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSRecording artist Miley Cyrus poses on the red carpet as she arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSRecording artist Nelly Furtado poses as she arrives on the red carpet at the 2012 Billboard Music Awards in Las Vegas, Nevada May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSModel and actress Amber Rose arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSSinger Monica arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSLisa Marie Presley arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSActress Zooey Deschanel arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSActress Julianne Hough poses on the red carpet as she arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSSinger Brandy Norwood arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
www.photopress.at9105313 The 2012 Billboard Music Awards at the MGM Grand Hotel and Casino in Las Vegas, Nevada on May 20, 2012.Pictured: Carrie Underwood
REUTERSSinger Justin Bieber arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSSinger Usher arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSSinger Taylor Swift arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSModel Chrissy Teigen arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)
REUTERSSinger Jordin Sparks poses backstage at the 2012 Billboard Music Awards at the MGM Grand Garden Arena in Las Vegas, Nevada May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT SOCIETY)
REUTERSSinger Natasha Bedingfield poses backstage at the 2012 Billboard Music Awards in Las Vegas, Nevada May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-BACKSTAGE)
REUTERSSinger Alicia Keys arrives at the 2012 Billboard Music Awards in Las Vegas, Nevada, May 20, 2012. REUTERS/Steve Marcus (UNITED STATES - Tags: ENTERTAINMENT) (BILLBOARD-ARRIVALS)