I guess you haven't heard that Warner Bros. has already greenlit a Superman sequel,
The fate of DC movies rests on this movie.
If this fails then expect a Batman reboot to be quickly greenlit to rebound from "Man of Steel's low performance.
based on the advance buzz and box-office projections.
It's common these day's for studios to line up a sequel before their movie is even completed.
It's a sign they're positive about the movie
If the movie fails then they'll quietly back away from sequel talk till no one remembers.