I use it for keeping up with distant family and HS friends. I will say that I REGULARLY check the privacy settings. They tend to make changes to the program that ends up changing how people access your information. Now I'm not a huge privacy freak but I do have pictures of my teen daughter and don't want those floating around the internet. I guess I'm a paranoid mommy :D
Oh....one other thing...you will get people requesting to be your friend, etc. DO NOT RESPOND to them unless you REALLY know them and want to know what is going on in their lives every day (ie: cousins, family, etc.).