Before this movie gets out is hard to know what is going to happen, this are theories based on the trailers.

Aquaman will know Superman from his Deadliest Catch days, since Aquaman will have to fit this universe, chances are he is some type of mutant humans that live in the ocean.

War will destroy Krypton.

Lex Luthor is going to be the President or at least on the run to be the President.

Kryptonite is going to be a mineral from Krypton, maybe used on their war weapons or caused by this war.

Batman or Lex will use a battlesuit from Kryptonian technology, in Batman cause is going to be the Ring that Superman give him, in this universe Superman knew the Ring idea was to damn lame too work, so he help him, so does Oliver Quinn and even maybe Lex Luthor, hey the world is darker, beside if Batman punches Superman in the face, Luthor would had a giant smile on his face.

Batman would had met Superman during his early year, before gettin in the Superman suit.

Brainiac = Kryptonian Skynet.

Mr. Mxyzptlk is going to have a "cameo", hey its Snyder, 300 and Watchmen show he uses crazy jokes.

There is going to be a joke about the fact Amy Adams was in one episode of Smallville, as a fat chick that his super power was being skinny, but that she needs to eat as much as she can, so she can stay skinny.

Superman is the first movie about this universe, but not the first Superhero of this universe, it would be chance The Spirit, Batman and/or Green Arrow decide to do this way before the Big Blue decide to be a hero.

Like the Joker said:

More powerful than a locomotive, and just about as subtle.