Mariah Carey and Nick Cannon are engaged, according to a source close to the diva, Access Hollywood reports. Cannon's rep had no comment on the report when reached by Usmagazine.com. Carey's rep was unavailable. Carey, 38, met the 27-year-old rapper-actor when he directed the video for her latest single, "Bye Bye," in late March. "It's hot and heavy," an insider told Us Weekly in its latest...