I made a facebook page when I moved back to my hometown after living away 6 years because the folks in my senior class from High School were working on a reunion and for the fun of it, were trying to get as many to sign on as possible. Part of it was fun.
I am not a frequent poster. I only have family members and people I actually know or have known in the past with only about 6 exceptions and I have it private, so people who are not on my list can't see what I post, not that I have anything to post about that anyone else would be jealous of... LOL ! I do like it for getting to see photos of my nieces and nephews and their young families and the such.
Through the years I have seen stories of others who have done somewhat idiot things online and lost their jobs or more and I am one that doesn't mind learning by other people's mistakes! I never list the name of the company I work for anywhere and avoid saying the name of it for any reason. No way I want to risk my livelihood.
I think this is where FB is ideal finding school mates etc, but everything else they can keep.