This morning, the LA Times Hero Complex broke the news that Warner Bros. has plans for the Caped Crusader to join in for the 2015 sequel to MAN OF STEEL. The Hollywood Reporter chimed in to confirm, and it looks like we're likely to see the team-up, featuring Henry Cavill in a reprisal of his role as Superman, along with a yet-to-be-announced Batman. David Goyer and Zach Snyder are also expected to be attached to this project.
Also rumored to be in development: a FLASH movie for 2016 and the much-awaited JUSTICE LEAGUE film in 2017.
We'll find out more after the Warner Bros./Legendary panel (currently in session!).
Update
The Batman/Superman movie is officially happening!
"Snyder is co-writing the story with David S. Goyer, who will then pen the screenplay. Production is expected to begin in 2014, with an anticipated release date in Summer 2015."