There is no information about when exactly we might expect the game, but 2016 is definitely out of the question at this point. There’s no way Bethesda would be able to wrap up development on the title that quickly if they aren’t actively working on it at the moment, plus there is still more to come for “Fallout 4” as well.
Whether or not 2017 looks more plausible is hard to say at the moment, but it’s not impossible for the studio to manage that kind of release. There are rumors that another game might come before that, such as “Dishonored 2”, which would make 2017 seem far less likely if it turns out to be true.
The studio should definitely take their time and make sure that the release matches the expectations of their fans fully. There is no rush to get it out faster, as everyone seems patient enough to wait for a few more years right now, especially with so many other good games on the market.
“Fallout 4” also showed that no matter how highly a game is anticipated, it can always fail in some regards. So Bethesda will, in all likelihood, wait as much as possible for the release of this game and they will study the market carefully before bringing it out. That might also mean delaying it a bit artificially just to release it at a better time though, e.g. waiting a little if there are too many fantasy-themed RPGs coming out at a given time.