Classical pop singer Josh Groban is used to performing in front of millions of people everywhere — from the Oscars to the 2002 Salt Lake City Olympics. But all of that paled in comparison to his most recent gig — singing in front of President Barack Obama at his Inaugural celebration concert on Jan. 18.Groban, 27, was one of several celebrities and performers, including U2, Beyonce, Mary J. Blige, Sheryl Crow, Bruce Springsteen and Stevie Wonder, who stood on the steps of the Lincoln Memorial at the We Are One: The Obama Inaugural Celebration."I was very nervous," Groban told OK! at the Huffington Post Pre-Inaugural Ball on Jan. 19. "Heathy nerves though. I ... Read More >>