At this time, Facebook has offered no official statement on how the glitch happened or how widespread the email issue was. Reports of the email issue first started coming in via Twitter posts and Facebook status updates.
To facilitate the migration from the Facebook of today to the advertising maven that Facebook hopes to become in an effort to generate cash, changes in privacy settings are needed. In December 2009, Facebook announced serious changes to its privacy settings that made more of the information in a users profile searchable and viewable by the public. This privacy change led to outrage by many users and privacy advocates. Facebook CEO Mark Zuckerberg stated in January that people no longer have the same expectations of privacy online. Facebook isn’t alone in privacy issues though; Google learned the hard way to ask users before it makes information available to other users when it launched Buzz. At first, the Buzz service made email histories available to a large number of users without specific permission from the account holder.