Jacob Appelbaum, hacker, former Wikileaks volunteer recently told not to register on Facebook if you do not wish surveillance organized on you. He admitted, you will give out sensitive information even without your consent - if you have even a couple of friends who may tag you on pictures.

To be even more precise, even if you do NOT register, you might be tagged - but that is just another part of story.

Also Jacob says, Facebook is the greatest database of Jews, leftists, right wing people and anyone else in the world, who may be targeted one day after the governmental change.

There still is one way to use it through IP substitution tools like TOR and inserting false data, having false friends, making information other ways useless. But is this the reason millions of people use it so much?