It's certainly possible, but there are stronger industry rumors that Rocksteady are working on a Superman game instead. I tend to think it's too early for them to reveal their next game, though, as they probably only went into full production a year ago.
They're not working on Superman. An insider, as far as I know anyway, here confirmed as much and Nirolak and folks have dug job listings for multiple weapon modelers to online co-op I believe. It honestly sounds like it could be either Justice League or another WB property like TMNT or The Matrix?
WB Montreal was more strongly tied and rumored for Superman but who knows what's going on there.
Rocksteady said they would be talking "soon" and that was about a month or so back. Their social media pages fired back up too with retrospectives and throwbacks to their previous games - a track record of something they did before prior to revealing a new Arkham title. So it seems like just a matter of time until they make a announcement...