10. When?
The chronology of events will be vital to successfully connecting the continuity of The Dark Knight Trilogy to the events of a Justice League film. During the time frame of the Batman Begins, The Dark Knight, and The Dark Knight Rises, we are given a time span of roughly 9-10 years within the context of the story. There are no mentions whatsoever of any other superheroes, alien lifeforms, or even other cities within the DC universe that one would expect to see or hear about in an eventual Justice League film. There was never even a mention of Metropolis. Since there is nothing prior to the events of The Dark Knight Rises that would require the filmmakers to address in a Justice League film, the easiest assumption would be that the film will take place sometime after those events. The story of Man of Steel could address part of this question but with that film not due for release for almost three more months, we will have to wait and see. After all, if Superman was present and active during Bane's several month occupation of Gotham City, don't you think he could have resolved it in about five minutes?