I recently rediscovered this video from the American Civil Liberties Union, via Wired UK. It illustrates very quickly and simply why privacy is important. It was produced in 2006, when Facebook was limited to college and high school students and before Google acquired YouTube. Amazing how much has changed since then, and not all of it particularly benign if you have any concern over how these and other private entities may potentially share your information.
I believe that the people’s lack of awareness of how much personal information they may be passively broadcasting into the cloud has been accelerated by the growth of the mobile web. Whilst everyone can understand the (probably minimal) risks associated with location-based check-in services such as FourSquare and Gowalla, there seem to be a number of apps sharing information without providing full disclosure to users that they are doing so.
The real problem here is the ease with which users can install mobile apps and rapidly click through the data permissions. We’ve all been doing this for many years with software EULAs. Of interest would be how much of this is due to developer carelessness, and how much of it is deliberate.