From BA Digest:
There's one thing I believe with certainty: Warner Bros has no idea how to approach the Justice League movie.
I've now heard from multiple sources that the Will Beall script for Justice League has been scrapped. The story from each source is the same: it's terrible. Some sources seem to think the whole movie is going to fall apart and never happen, while some believe that Warner Bros will keep moving forward, unwilling to lose the superhero arms race.
That being said, I think it being tossed out could more or less be due to Gangster Squad not doing well.