How did Google+ get 100M active users? Hint: they’re not reading your posts

Google (s GOOG) SVP of Engineering Vic Gundotra revealed some impressive stats about Google+ earlier Monday: The service now has a total of 400 million registered users, and it just surpassed 100 million active users. Gundotra made these comments while announcing the purchase of Snapseed maker Nik Software, and the stats were obviously meant to deal with the often-repeated notion of Google+ being a ghost town. However, the number of active users in particular doesn’t mean what you may think.

Here’s what Gundotra said in his post on Google+:

While Google+ is all about creating a better experience across Google, it’s also a destination. And here too, I’m happy to report that we have just crossed 100,000,000 monthly active users on Google+ ( and mobile app).

This may sound a bit like there are now 100 million people posting to and reading posts on Google+, but the reality is somewhat different.

Google began to unify its messaging products at the end of July, replacing the traditional Google Talk video chat experience with Hangouts. The upgrade was rolled out gradually, but by now, most users should by default launch a Hangout whenever they’re starting a video chat from GMail or Google Talk. And, guess what: Hangouts are part of Google+, which means that each video chat automatically takes you to

It’s unclear how many of those 100 million active monthly users simply visit as part of a video chat as opposed to actually browse through profiles and posts on the site. Gundotra didn’t break out any specifics about the data, and a Google spokesperson wasn’t available for comment on the matter. However, one can assume that the timing of the active user milestone shortly after the Hangouts integration is no coincidence.

Google has gotten plenty of criticism in the past for releasing less than transparent numbers about Google+, and the critics will likely eat this one up as well. However, the issue also shows how difficult it is for Google to compare Google+ to competitors like Facebook(s FB).

Google has long positioned Google+ as a social layer that permeates all of its other products. That’s very different from Facebook, and it means that Google needs to spend more time explaining the network and its unique benefits and features. Otherwise, we might one day all be using Google+ — but still think that no one is using it.