Zack O'Malley Greenburg, author of "3 Kings: Diddy, Dr. Dre, Jay-Z, and Hip-Hop's Multibillion-Dollar Rise," discusses how hip hop moguls, Jay-Z and Diddy, leveraged their fame to create two million-dollar brands. Jay-Z launched Armand de Brignac and Diddy has a deal with Diageo's Ciroc vodka.