Exactly.
I avoided facebook for almost 2-3 years. Then someone I know/knew (never found out who), decided to impersonate me on Facebook. Then one of my friends finds out i "have" and account, and tells my new girlfriend, who promptly gets really pissed off at me for having a facebook account and not friending her.
I ended up making a facebook account just to avoid this kind of situation continuing (and i reported the imposter, who promptly removed themselves from search, and facebook ui bugginess prevented me from copying their account id number, etc (I hit block when they friended me, and then went to hit the 'report' button, but their page rewrote itself and removed the entire chunk of html before i could get close to clicking the report button)
Now i find out google's got a facebook clone, and all my friends are going nuts about it. And i find out "oh, don't worry, you're already listed in a bunch of my circles". Which means, i presume, i'm being tagged on shit, with no control, unless I sign up. Awesome.
This entire system can fuck itself.