Google: Why I joined Google+ and deleted my account 45 seconds later.
Thing is, I forgot why I dropped out of those, and it really had less to do with privacy than with this: There are just some people who I never want to talk to again. I know that sucks, but it's true. When I first logged onto G+ I was excited. "Wow, Matt's joined. And he's already got 12 friends! Hey, my mom's on here?! And Alex...awesome."
Then I started scrolling down the list and saw a face I just really didn't need to see again. Then another, and another. Not because I hate them or fought with them, but because they're the kind of people who just talk endlessly without saying anything, and waste my time. And while I have nothing to say to them, I'm not enough of a jerk to be cold to them if I run into them at a party.
I've got no problem being a total dick to people I hate. I got that covered. But when it comes to people I just don't want to spend time with, I do what most normal people do -- I'm polite but distant, and I make sure their access to me and their demands on my time are as limited as possible. E.g. I don't give them my phone number when I move, and I try not to let them see my photo every time they open their web browser.
So basically, I just deleted my account because as much as I'd like to join the hangouts with my friends, I don't want some people to see me, because then I'll have to be an asshole to people I'm just ambivalent about.
I gotta say, I'm a little offended by your audacity, because you're essentially asking me to categorize every single person I've ever had an email conversation with as a friend or a non-friend. That wouldn't be much fun the next time I run into them at a party or a show, would it? But I'm not sure you care about this, since your revenue stream is from commercializing the data that arises from your provision of these relationship metrics.
So again, I do have great respect for what you've done with the interface and whatnot... but the demands that would be placed on my time (and the intrusion into my comfort zone by people I don't want to talk to), all of which are automatically incurred by signing up for your service, would cost more in billable hours than the service is worth. And that's why I'm leaving.