It was just recently announced that master director Christopher Nolan would be directing his next movie and it will be set for a release sometime next year. What's crazy is, some people think it's actually the Green Lantern Corps movie—and the theory makes a lot of sense.
This comes from The GWW's Thomas Polito:
To recap, Nolan's film will have Robert Pattinson and John David Washington as the leads, and they could very well be playing Hal Jordan and Jon Stewart. The film is also said to be looking for an ‘age-appropriate female lead' (Star Sapphire) and an older male co-star (Sinestro).
There's also another thing: the movie is being described as a "massive, innovative, action blockbuster," which could very well describe any upcoming superhero film.
Of course, it's very likely that this isn't the Green Lantern movie, but unless we get any official announcements, this is probably my favorite piece of speculation that's currently online.
As for the factors going against it, you would think that DC would have made an official announcement about the film seeing that it's one of the biggest heroes (with one of the biggest directors) of DC. Plus, if the movie is going to start production this year, it would need at least an extra year to work in all that superhero CG—unless Nolan is making a low-budget, practically shot Green Lantern movie.
If any case, they could be holding off on the GL news to give focus to Shazam!, but what are the odds?
For now, expect Nolan's next movie to come out July 17, 2020.