Katy Perry Lady Gaga Ke$Ha Rihanna Adam Lambert Estelle Demi Lovato Carly Rae Jepsen Bruno Mars Pussycat Dolls 3oh!3 Ellie Goulding Christina Perri Lily Allen Carly Rae Jepson Sara Bareilles Tove Lo The Script September Runner Runner Bridgit Mendler The Wanted Natalia Kills Kate Voegele Allstar Weekend A Fine Frenzy Kate Nash Anne-Marie David Archuleta Eminem Kelly Rowland Michael Jackson Shawn Mendes Glee Cast Carly Rae Keri Hilson Victoria Justice Far East Movement Megan Traynor Bruno Mars & Hooligans Mkto Miley Kesha Cole Coldplay Call The Cops Sia Furler Weatherstar Armin Van Buuren Kanye West