Megan Wollover, left, and host Tracy Morgan arrive at the Billboard Music Awards held at the MGM Grand Garden Arena in Las Vegas. (John Shearer / Invision / Associated Press)
Jennifer Lopez (Robyn Beck / AFP/Getty Images)
Chris Brown (John Shearer / Invision / Associated Press)
David Arquette (John Shearer / Invision / Associated Press)
Chad Kroeger and Avril Lavigne (John Shearer / Invision / Associated Press)
Alyssa Milano (John Shearer / Invision / Associated Press)
Jason Derulo (John Shearer / Invision / Associated Press)
Shania Twain (Jason Merritt / Getty Images)
Psy (Jason Merritt / Getty Images)
Taylor Swift (Jason Merritt / Getty Images)
Hayden Panettiere (John Shearer / Invision / Associated Press)
Kelly Rowland (John Shearer / Invision / Associated Press)
Z LaLa (Robyn Beck / AFP/Getty Images)
Jenny McCarthy (Jason Merritt / Getty Images)
Wiz Khalifa and Amber Rose (Jason Merritt / Getty Images)
DJ David Guetta and Rapper Akon (Jason Merritt / Getty Images)
Jennifer Nettles (John Shearer / Invision / Associated Press)
Miguel (John Shearer / Invision / Associated Press)
Carly Rae Jepsen (John Shearer / Invision / Associated Press)
Stana Katic (John Shearer / Invision / Associated Press)
Emmy Rossum (John Shearer / Invision / Associated Press)
Nicki Minaj (Jason Merritt / Getty Images)
Kesha (Robyn Beck / AFP/Getty Images)
Jennifer Morrison (John Shearer / Invision / Associated Press)
Caroline Hjelt, left, and Aino Jawo, of musical group Icona Pop (John Shearer / Invision / Associated Press)
Sky Blu of LMFAO (John Shearer / Invision / Associated Press)
Miley Cyrus (Jason Merritt / Getty Images)
Chloe Grace Moretz (John Shearer / Invision / Associated Press)
Selena Gomez (John Shearer / Invision / Associated Press)
Neil Perry, left, Kimberly Perry and Reid Perry, of the Band Perry (John Shearer / Invision / Associated Press)
Mike Tyson (John Shearer / Invision / Associated Press)
