Do Not Track is a step toward putting you in control of the way your information is collected and used online. Do Not Track is a feature in Firefox that allows you to let a website know you would like to opt-out of third-party tracking for purposes including behavioral advertising. It does this by transmitting a Do Not Track HTTP header every time your data is requested from the Web.
Can anyone even imagine Facebook doing this?
I hope this finds its way into WebKit. “Do Not Track” is also available as an option in Safari 5.2, which is available to developers right now. (thanks, Jesper)