'Justice League' is coming out in 2015, which is already going to be one of the biggest summers for event films (between it, 'The Avengers 2' and 'Star Wars Episode 7'), but other than Henry Cavill rumored to appear as Superman none of the other cast has been fleshed out. The latest hot rumor is that Joseph Gordon-Levitt will play Batman, the Dark Knight himself.

UPDATE: Hollywood.com reports that reps for Joseph Gordon-Levitt have recently denied his involvement in the 'Justice League' movie, and therefore his cameo in the 'Man of Steel' flick. Still...

This comes from Drew McWeeny over at Hitfix, and considering what happens in 'The Dark Knight Rises,' it sounds like a solid rumor. For those who haven't seen 'TDKR' the rest of the paragraph is spoiler territory: At the end of 'The Dark Knight Rises,' Bruce Wayne's Batman has retired and Gordon-Levitt's John Blake (revealed to be really named Robin) looks like he's about to take up the mantle. With Christian Bale swearing he wouldn't return without Christopher Nolan, and with the franchise having set up Gordon-Levitt as his successor, this makes a lot of sense.

And it sounds like a good fit as it will give some continuity to the universe, while also setting up the next set of Batman films in a way that continues the Nolan universe of Batman without needing Nolan at the helm. But wait, there's more. McWeeny suggests that we may get Gordon-Levitt and another performer in an additional movie, perhaps even before 'Justice League.' McWeeny hints that it's possible that DC has taken a page from the Marvel universe and wants to start tying the films together. If so we could see this new Batman appear somewhere in next summer's 'Man of Steel.' For now this is just a rumor, but it's a pretty great one.