According to Kotaku sleuth Superannuation, another Rocksteady Batman title is coming next year.
The text in several agency job postings by an unnamed British developer matches that of some Rocksteady openings, and tips the game for a 2014 launch.
On top of that, earlier this year long-time Batman voice actor Kevin Conroy let slip at Dallas ComicCon that he was working on a new Arkham title that was not Arkham Origins.
According to Superannuation, should another Batman title appear next year, it could point towards an annualisation of the series.
Warner Bros. Montreal began development on Arkham Origins at about the time Rocksteady's Arkham City released in 2011, and with two studios working on two-year turnarounds, such a release schedule is certainly achievable.