How does Batman make any sense in a Man of Steel sequel? Bruce Wayne, maybe. But a guy dressed up as a bat? A coworker of mine, who happens to collect comic books, wasn't too thrilled about this news. As he said, "How useful would Batman have been in Man of Steel? General Zod vs Batman?" I told him Bruce Wayne could have some sort of business/military thing going on.
As far as actually donning the bat suit, I'm not sure how that works in a Superman movie.