Bruce Schneier on privacy:
To the older generation, privacy is about secrecy. And, as the Supreme Court said, once something is no longer secret, it's no longer private. But that’s not how privacy works, and it’s not how the younger generation thinks about it. Privacy is about control. When your health records are sold to a pharmaceutical company without your permission; when a social-networking site changes your privacy settings to make what used to be visible only to your friends visible to everyone; when the NSA eavesdrops on everyone’s e-mail conversations–your loss of control over that information is the issue. We may not mind sharing our personal lives and thoughts, but we want to control how, where and with whom. A privacy failure is a control failure.
Schneier nicely sums up why I have such an issue with Facebook. Facebook allows users the ability to control what they share, but at the same time seem to have no qualms about sharing that information with third parties (including sensitive data like phone numbers and addresses). Twitter is different: everything, unless it’s a DM or a locked account, is public. Facebook carries a different privacy expectation than Twitter: since it’s all assumed public, people don’t say or share things they don’t want to be heard. Facebook is theoretically limited to your friends, but the service continues to violate user control over their data.
I would submit that Jeff Jarvis is correct: there is a confusion within Facebook between a public and the public. When I publish something on this blog, I’ve made it immediately available to the public. But if I update a status on Facebook, the assumption is I’ve made that available to a private public of my own creation. Facebook continues to push the line of public and private on the Internet, but never defined where that line ended (by contrast, at least in theory, Google always promised its customers it would “not be evil”). Certainly being public can be a good thing – governments and corporations, for example, should strive towards transparency – plus there is value in being more public and sharing collective wisdom. I support publicness, but also will defend control over our private publics.