They really dropped the ball with the marketing on it, starting right from the beginning leaving mars out of the title. Why would anybody who doesn't know what it is go to a movie called "John Carter". Just the name sounds boring. Which is why if it did skew older, I'm not all that surprised. You're not going to draw in teenagers with something that seems vanilla, whether the movie itself actually is or not. Still, it was not nearly as soft an opening as I expected. The question now will be the drop over the next few weeks. That all depends on word-of-mouth. In the end, though, I'd also be surprised to see over 100m domestic, too. Which might cover their panicked marketing blitz from the last month or so.
Disney's in a bit of a tailspin right now at the theaters.