So by January, Affleck will be directing, right?
Basically. And if he's not directing, he will be supervising producer.
Hmmmmm. I may actually want to see this movie.
So, I'd heard whispers, and now I believe it to be true. There is ONE reason and ONE reason alone that Affleck was brought on to this project: He is to be the Joss Whedon of the DC film universe.
There were reports that Affleck (which he sort of confirmed) was approached to shepherd a Justice League film. By moving out the Nolan parts (such as Goyer, who was once the GO TO for these films) and moving in some of the Affleck parts, don't be in any way surprised if Snyder also leaves over "creative differences" or "not enough time to do x,y,z" And Affleck, in the interest of ensuring the film reaches completion on time, takes over directing duties.
Am I saying that will happen for sure? Not quite, however, I think if it doesn't happen on this film, it will absolutely happen with the full Justice League film, which this upcoming film is a clear precursor to.
Affleck and his team have been brought on for the world building that Nolan, et al, were either unwilling or unable to do. At this point, Snyder is nothing more than work for hire.
Here's my (uninformed) take: Affleck is a prized WB asset. As a director, he's probably closer to the grounded style of Nolan than Snyder. MAN OF STEEl did OK, but could've done much better. If Affleck wanted the director's chair, they'd probably give it to him. However, the big "if" is that Snyder was Nolan's pick (or, Nolan had big input into it), and to move him aside might upset WB's one of two biggest asset, Nolan (J.K. Rowling is the other biggest).