One More Nexus 5 Android M Developer Preview
Google recently released its second Nexus 5 Android M Developer Preview. And unlike Apple, we know exactly what's coming to the Nexus 5 and Google's other Nexus guinea pigs in the future.
The company has outlined its Developer Preview release timeline in detail and its stuck to the plan thus far. The timeline calls for an initial release in May (that happened), a Developer Preview 2 in June/July (that just happened), and a Developer Preview 3 in late July (this hasn't happened, yet.)
Google says that the unreleased Developer Preview 3 will be a "near final" version of the update. The company hasn't announced a specific date for the release and there's a very good chance that it will be released without any kind of warning.
Once the Developer Preview 3 is released, we probably won't see any more betas. That's because the final release is expected to come directly after the third preview.