From a conversation with a friend who feels uncomfortable posting things publicly on the Internet. It's something I've been thinking about lately, given the prominence of social networking as one of the hot topics in software.
The social landscape of the Internet and the amount of private data floating around is very different today than it was nine years ago when I started my LiveJournal. I've always felt that it's easiest to be public with most information. Keeping track of who's allowed to know what, presenting a different face to different people, letting information spread by rumors and slips of the tongue... that's all a lot of work and often ends up in a big pile of drama. It's much easier to let anyone know who cares. This also creates an opportunity to discover shared experience: when everyone can see what everyone else is doing, we can let clever solutions spread through the cultural zeitgeist.
But I also believe firmly that this publicity has to be by choice. Information should be shared because people want to take part in a community of shared information and communities work best when everyone is comfortable being a member. My favorite high school teacher, during Socratic seminars, would put a picture of fish on the floor in the middle of all the tables as a reminder that it's fun to come to the pool and watch everyone swim around, but it's a lot more fun if you jump into the water. Publicity by choice is related to a maxim I adapted from Stan Brakhage: the freedom to leave is one of the most fundamental.