My guess is instead of the war with Earth 2 from Future's End, the "real" history will be a Prime Earth/Earth 2 team up against a common threat, and that will be this story.
So 2015s event in March is basically the temporary editor's project?
I'm still waiting for some buzz for this event before I pick up Future's End (or not).
Here's wishing Defalco the best of luck on trying to make the new 52 of DC Comics make sense.