Mariah Carey might be keeping silent about the $2.5 million 17-carat engagement rock on her finger, but her new beau isn't. Actor Nick Cannon was overheard yesterday saying the pair are going to marry, reports the New York Post, during a follow-up visit to the New York jeweler where he purchased the bauble. "Maybe he's making payments on it," laughed the Post's source. Carey started sporting the ring last week. (More Mariah Carey stories.)