In 2006, Superman Returns made 200 million in the U.S. and 391 milllion worldwide and got positive reviews from critics. Warner Bros. said they were hoping for 500 million worldwide.
In 2013, Man of Steel will need to make at least 400 million to beat Superman Returns disappointing box office. The Avengers grossed 1.5 billion, and the Dark Knight and the Dark Knight Rises grossed over 1 billion a piece.
Warner Bros. is in need of a franchise:
Harry Potter is done. Nolan's Batman is done. The Green Lantern flopped. The Hobbit is being stretched into 3 movies to make it seem like Warner Bros. actually still has a huge franchise left.
Will Man of Steel be a success if it only barely surpasses Superman Returns gross. Incredible Hulk barely passed Hulk's gross and Marvel Studios has no plans to give the character another film anytime soon.
How much does Man of Steel have to make for Warner Bros. to go forward with more DC films that aren't Batman?