There was a double dose of Britney Spears at Sunday night’s Billboard Music Awards in Las Vegas. The ultimate showgirl opened the evening with Rihanna and later joined tour mate Nicki Minaj for an encore performance.Musicians weren't the only ones in the spotlight during the show. "Modern Family"'s Eric Stonestreet was debazzling as an Elvis impersonator, along with master of ceremonies Ken Jeong, star of 'The Hangover Part II.'Perhaps the moment frozen in fans' minds is the kiss shared between young Hollywood couple Justin Bieber and Selena Gomez. The two shared a tight embrace when Justin won his first award of the evening for Digital Artist of the Year. When his name was called again, this time to accept for Top New Artist of the Year, the lovebirds locked lips while the cameras rolled. On the red carpet, Selena revealed that she plans to include her beau in the thank you section of her album booklet. Backstage, Justin called his special lady "amazing." (ETonline.com)