Is it all that likely that there will be a Bond film in 2017? Will we ever get one every two years again?
As long as EON keep playing it by ear, then I'd say it's unlikely.
But, if EON were to plot out the direction of the series two or three films in advance, then I think two year gaps are certainly realistic. EON's problem, the way I see it, is that they are too afraid to simply go with their gut, instead opting to "see how the current one is received" before moving forward. While there is certainly value in taking a step back to evaluate how things are going and the direction to take the series, I think this can be done, say, every five to seven years, and not after each and every film. One almost gets the feeling EON are convinced that if they make a gamble by plotting subsequent installments ahead of time, the general public will not take well to their approach, and the film(s) will flop.
Here is where I make a radical, yet modest assertion: Bond movies are, for the most part, guaranteed box office hits. The general public does not particularly care what the plot is, so long as it is executed well. In fact, I think EON abandoned the entire Quantum thread solely because they misconstrued the general public's negative reaction to QoS as stemming from "people did not take well to Quantum as an organization," when, in fact, it was probably more technical issues (editing, etc...). In other words, Quantum was not the issue with the film; the execution of it was.
If they really are so intent on making the Craig era one unified continuity, it would do well to plan the films in advance, rather than contrive plots solely after seeing how the previous entry fared at the box office.
Here's hoping my post does not spawn too much outrage...
