Google keeps trying to make Google+ happen. Now it's taking an extra step to encourage you and your friends to connect over your favorite Android apps in the Google Play store.
Google added a page called My Play Activity. It displays a list of all the Play Store content you've reviewed and shared—kind of like Yelp for Android apps. It sounds like it's meant to help foster a community where users can bond over favorite apps and connect in that manner, but it also helps you check out what your friends have been downloading lately. It's a little like the Google Games app portal, except that it includes applications of all types—so it's more like an expanded version of the recent activity panel in the Google Play app for Android.
Apparently it's a slow rollout, so if you don't see the page at first, refresh and try again.