Elementary's development process
The team behind elementary OS gives a look at the development process on their blog to help answer the inevitable question of when their next release, codenamed Loki, well come out. It's a fascinating read. They still don't (and won't) give a release date, but they offer clues:
When we release Beta 1, it is for developers and testers to help us find any major regressions before we release the stable version of Loki (called GM or Grand Master). The Beta1 milestone represents a kind of “home stretch” where we wrap up big features and get the OS ready for translations, screenshots, and documentation. This is what we’re working on right now. Depending on how Beta1 goes, there may or may not be additional beta releases.