You need very few weeks for the official launch of 6.0 Android Marshmallow. According to rumors his presentation would be in three weeks, on Tuesday, September 29, at the presentation of the new Nexus.
Of 6.0 Android Marshmallow We already know practically all news thanks to the Developer Preview 1 M, M Developer Preview 2 and M Developer Preview 3 that came to the Nexus. But they are not all innovations, since Android M missing more innovations, such as Marshmallow Easter egg and your debugging icon.
The Marshmallow debugging icon already we can delete it from the list, since it has already leaked. A developer of Google published a screenshot in a group of development of Chromium showing the icon of the new version of Android Debug, as we can see in the screenshot is one cloud with eyes and antennas, in line with eyes and antennae of Lollipop lollipop.
And about your Easter egg… He has appeared on the net this image claiming to be Marshmallow Easter egg but many doubt so, since it is the same as that of Lollipop, just changed the lollipops for the debugging of Marshmallow icon.