A sequel to 2009's LEGO Batman has been known since the summer, around the time LEGO and DC Comics (and Marvel) were revealing their plans for more super heroes in the toy line. Now a LEGO fan site says the title will be something like "LEGO Batman 2: DC Super Heroes" if that image is on the level.
That's Superman, Luthor and a tiny Joker (I think) in the background of the box shot, showing Batman in what appears to be the Michael Keaton-style all-black batsuit. Other reports have said Green Lantern and Wonder Woman will appeear in the game, due for release next year.
LEGO Batman 2: Super Heroes Video Game [BrickTuts. h/t Ursus-Veritas]