Facebook's online poll crosses a line

[Commentary] Not content with more conventional ways of expressing disapproval, an unidentified Facebook user recently posted a poll asking whether President Obama should be assassinated. The poll was outrageous, and Facebook forced its removal even before the Secret Service called. The larger questions raised by the incident, however, are how much control companies should exert over the use of the megaphones they provide online, and how much information social networks expose about the people who use them. Facebook gives developers the ability to collect a stunning amount of information about the people who use their applications. Unless they're savvy enough to change their privacy settings, users not only automatically reveal the personal data they've entered into their Facebook profiles, they also disclose similar information from their friends' profiles. Those disclosures and connections could prove a gold mine to investigators, exposing people to scrutiny simply because a friend gave the wrong answer on the wrong Facebook poll. Before that happens, Facebook should do a better job of teaching users how to guard their privacy against the risks posed even by seemingly innocuous applications.