Information concerning Bungie and Activision’s contract was contained within the court case documents:     

We already knew that Destiny and Activision would be in a partnership for 10 years. However, what we were not aware of is that five games for Destiny would come out of it.

In the chart above, you can see the titles of the five codenamed projects. There are Tiger Projects 1-4, and one project with the name Comet 4. Disregarding Project Tiger 1, every project is meant to be released on September 30th of the years 2015, 2017, 2019, and 2020.

Though these are the projected release dates for the Destiny content, the original Destiny itself was delayed for a while. So we can only wonder whether those dates will shift or not.