The Olate Dogs canine act has been declared the Season 7 winner of the NBC competition series "America's Got Talent." The performing pups -- and father-son trainers Richard and Nicholas Olate -- won the top prize of $1 million. They will also headline a show in Las Vegas. Comedian Tom Cotter took second place in Thursday night's finale, which featured guest appearances by Blue Man Group, Justin Bieber, Green Day, Ne-Yo, Joan Rivers, Flo Rida and One Republic. The show's host is Nick Cannon, and its judges are Howard Stern, Sharon Osbourne and Howie Mandel.