Today I’m adding a new feature to address these problems, called Privacy Lock. Privacy Lock will make it impossible to add public bookmarks to your account in any form while the setting is turned on. It will also make private bookmarks appear without a dark background, so the site is easier on the eyes. — Pinboard Blog
Excellent new feature from my favourite bookmarking service and it just goes to show that not everyone wants (or needs) to have a social element. Sometimes we just want to keep our bookmarks in something other than our browser.