I'm always skeptical as to how you can truly, accurately measure engagement on something like G+ or Facebook. Sure enough, this study only measures "public" act

I'm always skeptical as to how you can truly, accurately measure engagement on something like G+ or Facebook. Sure enough, this study only measures "public" activity. If you're just measuring engagement by how frequently someone posts, I think that's a bit misleading. As cryptoz and RobAtticus alluded to, I rarely post to Facebook, but that doesn't at all say I'm not "engaged" through reading my friends updates, viewing photos, checking out articles they read, etc. Just because I'm not outspoken (or even narcissitic, ha) enough to post to Facebook every 5 minutes certainly doesn't mean I'm not engaged with it. What intrigues me more about the article, is the picture of "waning interest" in G+. My interest in G+ is certainly fading. I might log in one every week or two, and even then it's the same routine; I'll log in, see that it's still the same ghost town it was last week, and then move on. If I were Google, I'd be much more concerned about keeping people interested in G+, not focusing on how many posts people make or how many millions of people have "upgraded" to G+ only to never return.