Harry McCracken has a pretty good articulation of the conventional wisdom about Google+:
Google+ is exuberant. It’s fun to use. And yet I’m pretty positive I won’t spend remotely as much time in it as I will in Facebook. You might have already guessed why: My friends, family and acquaintances are all on Facebook, where they add up to a bustling community I enjoy being part of. More than any particular feature that Mark Zuckerberg and company have cooked up, it’s the people in my life that make Facebook, well, Facebook…
I don’t feel guilty about favoring the social network that feels more like an extension of my world. That’s Facebook. And since Facebook exists, I don’t have much of an incentive to pour more energy into Google+. The two services aren’t identical in particulars and emphasis — today’s Facebook seems to be built on the philosophy that everyone should share everything at all times, sometimes in an automated fashion, and Google+ isn’t like that at all — but ultimately, they scratch the same itch.
I don’t know much about itches, but I believe the conventional wisdom is wrong: from Google’s perspective, Google+ is not a social network meant to compete with Facebook. Rather, it’s an identity system that follows you everywhere.1
Think about it: what is more valuable? Inane chatter, memes, and baby photos, or every single activity you do online (and increasingly offline)? Google+ is about unifying all of Google’s services under a single log-in which can be tracked across the Internet on every site that serves Google ads, uses Google sign-in, or utilizes Google analytics.2
Every feature of Google+ – or of YouTube, or Maps, or GMail, or any other service – is a flytrap meant to ensure you are logged in and being logged by Google at all times.3
Google’s mission is ostensibly “To organize the world’s information and make it universally accessible and useful.”
That was once true, but a better formulation today is: “To organize user information and make it universally trackable and marketable.”
Make no mistake, Google+ has been a massive success. Credit to Google for their willingness to be misunderstood and portrayed as a loser even as they mine information Mark Zuckerberg can’t even dream of.4
Not that Google doesn’t love the social stuff, but that’s icing on the cake ↩
I was challenged on this point, and originally hedged, but I believe it’s true. It’s not clear technically how it would be done, but the terms of use for Google Analytics were amended to allow this. See this thread on Hacker News for both points of view. I’d love to be proven wrong and will change this if I am. ↩
And they’re successful! I’m signed in right now, and you probably are too. ↩
This is a tad hyperbolic; those ubiquitous “Like” buttons accomplish the same thing for Facebook ↩