It turns out that next fall Bungie will be launching a new franchise called "Destiny." They are making the game in conjunction with Activision, and it will be available at first only on Xbox 360 and Microsoft's new Next-Gen system.
Here are more details from Yahoo Games:
"Bungie has agreed to develop four 'massively-multiplayer style … sci-fantasy, action shooter games' in the Destiny franchise for Activision, with one coming out every other year starting next fall. In the intervening years, Bungie will release downloadable expansion packs (codenamed "Comet").
Exactly what the contract means by 'massively-multiplayer style' is something of a mystery. It's unlikely that even Bungie could produce a new online game every two years. One possibility is players will be required to authenticate their game online whenever they want to play, as is the case with the recently released Diablo III. There have been rumors that the next-gen Xbox will require all games to do this, which is also how the system will reportedly restrict used games.
The contract released in the court filing was signed two years ago, and it's entirely possible elements of it have been adjusted since then. Under the initial terms, though, Bungie's first game in the series will be exclusive to the Xbox and its successor for a year. PlayStation 3 owners will be able to try it out in 2014, though it appears PS4 owners may not be able to."
If you want to check out the actual contract between Bungie and Activision, you can check it out at the Los Angeles Times
here.