ATLANTIC CITY, N.J. -- A kid for Kimye: Kanye West and Kim Kardashian are expecting their first child.The rapper announced at a concert Sunday night that his girlfriend is pregnant. Kardashian was in the crowd at Revel Resort's Ovation Hall with her mother, Kris Jenner, and West's mentor and best friend, Jay-Z. West told the crowd of more than 5,000 in song form: "Now you having my baby."The crowd roared. And so did people on the Internet.The news instantly went viral on Twitter and Facebook, with thousands posting and commenting on the expecting couple.