Are they or aren't they? That's what everyone's wondering about Mariah Carey and Nick Cannon -- are they engaged? She was spotted sporting some major bling on her left ring finger at the premiere of her new movie, Tennessee at the Tribeca Film Festival this weekend.

We don't have the answer to that question, but we do know that Nick was at the premiere. So what, you ask? So he bailed on his own movie to support her! "He bailed on his own premiere to be here," an insider tells Page Six. "He didn't do any press for his film, Ball Don't Lie, and came to see Mariah." If that isn't love, we don't know what is!