ND are always working on 2 projects,.. they are just staggered. They will have started on whatever they intend to do next already but it will still be years out because they are almost certainly in pre-production phase. with that semi-mysterious stand along multiplayer they may even have 3 projects in the works.I am probably misremembering.
I know when the last of us came out, everyone was talking about them having two teams.
But I thought there was an interview later where they talked about that there aren't exactly two distinct teams. I am probably misremembering because I can't find the article right now. I was under the impression that people get moved around a lot and they might have most of the studio working on a game with prototyping on the side or they might have a couple of groups working on games.