Yesterday, Google made it official. The next version of Android will be Android 6.0 Marshmallow. At the same time, they released the third and final developer preview.
The Android 6.0 Marshmallow developer preview is only available for the Nexus 5, Nexus 6, Nexus 9, and Nexus Player, as well as some AOSP previews available for Sony smart phones; however, the final release will be available for more models.
I decided to have a quick look at Android 6.0 Marshmallow. Have a look.