I still use facebook, but I have pruned my "friend" list to the half dozen or so who play Fish Wrangler with me. I periodically "Like" pages (eg seriouscompacts, pentaxforums, camera house, pentax snaps australia etc) but rarely post photographs ever since the first fiasco when it seemed that the security and privacy policies allowed companies to use your stuff for their own ends. Thery changed the wording so it appears you retain ownership but ever since then I have not trusted Zuckerberg or facebook to respect my ownership of my stuff (any stuff... not just photographs). I NEVER post a full res photograph publicly anywhere but particularly not on facebook.
I also discovered an app (Exfoliate) on Android that can go through your facebook account and delete all your comments on your stuff and other people's stuff, all your posts etc. Its only marginally effective, but it makes a very large task quite manageable when you go back into facebook to do manual deleting. This is why I will always have at least one Android device, even though I am an iPhone fan.
Back to the facebook thing... I dont think its any worse or any better than Google+, myspace, etc. Its all about getting information and selling it, one way or another. Google is much more insidious, and I still use it. I've kind of given up giving up on social networks, because if you are out there on the internet, you're visible. If you do a search on your real name or your nickname, you may be surprised at where you pop up.