He's a huge part of 'Earth 2,' he's going to be a huge part of the DC Universe, and everything he does from the Annual onward will have huge implications for the DC Universe. This isn't some new person coming in to be Batman. This is definitely a part of Batman lore.
But who is he?
We still don't know, but DC has stoked the fan flames by premiering a pair of pages featuring artist CAFU's take on the new Dark Knight from "Earth 2 Annual" #1 on their official blog, The Source.
The official synopsis for "Earth 2 Annual" #1 is:
The new Batman of Earth 2 debuts as The Atom begins a mission to lead a new team of heroes—but are any of them prepared for the threat they’re about to face?
So...who is he? We'll hopefully find out in "Earth 2 Annual" #1 when it hits shelves on May 29.