...is a question I've been asking myself for some time. I belong to Facebook simply because of my kids/nephews/nieces - it helps keep up when they're away - but don't post myself. Also, people keep asking me to "be their friend", and it seems churlish to say no. But I feel there's something sinister about both Facebook and Twitter, and I can't quite put my finger on it.
It could well be the speed with which posts are put up, especially on Twitter. People don't seem to think through their remarks, and some thoroughly nasty "tweets" have been aired. Others, as far as I can see, are just plain boring, and the rush to "tweet" tragedies and accidents (rather than perhaps seeing if help is needed) seems to me to be deeply unpleasant. I know some of these on-the-spot missives have proved very helpful, but others have been salacious, unkind or unncessary. At the other end of the spectrum, if I want to know badly enough what someone had for breakfast, I'll phone them (but don't hold your breath).
Some might say that I blog, and what's the difference? I suppose it's that not many of my friends, let alone my acquaintances, know or care about my blog, and it seems somehow more private. And while not everything I write is particularly sensible, at least with blogging there's time to think through what's written before it is posted.
(Breaking news: for lunch I had a sandwich and an orange.)