We initially thought that the appearance of Collections was happening with the Google+ update that was published today on Android, but I went ahead and installed it and am not seeing the option for Collections. As you can see, some people are. My guess is that the new Collections feature is controlled server-side rather than through the app itself.
So what’s new since our last report? Not much! Collections is exactly as we reported last week – a new feature for Google+ that allows you to group posts, photos, videos, links, etc. by topic instead of by person. It’s like the opposite of a Circle, in a way. Other people can follow your Collections or you can go browse the world’s Collections as well.
Collections was previously in a private beta or testing group, but if it’s showing up in the app to new users, we must be getting close to an official launch. Let us know if you are seeing anything related to Collections!