The only social media site I have ever used is Facebook, and I actually find it useful. It let's me keep up with going on in the lives of close friends and family, we can exchange interesting or funny stuff we find on the web, and I also have “liked” a lot of sites and that keeps me up with new happenings, material, and in the case of public radio program Facebook pages alerts me before hand to broadcasts I might want to listen to. I do have a very small set of “friends” though, just people I really know well and like in real life.
Some of my family and friends on Facebook really seem to lose any sense of proper restraint in their posts though. These people also seem to have a huge lists of “friends” as well, often in the 100s. The deeply personal information that they essentially broadcast to 400, 500, 600 people, most of whom they only know on line, astounds me. In an extreme example I never saw anything before like all the back and forth of a very messy divorce put out there by a splitting couple. Add into that all the comments from many of both of their “friends,” often “friends” of both, and what a soap opera.