I disagree with many of the arguments you make to support your theory, namely 1)the idea that the way users use Facebook wont evolve and get more sophisticated as they share more information, and 2) the idea that sharing more information about yourself even makes you more susceptible to stalker and hate crimes.

After I read your post, I went back up to the top re-read your proposal, which, in its simplest form, makes a the claim that reads: "Facebook-as-a-business will eventually kill the very users it needs to survive, because in order for Facebook to grow and profit, it will encourage users to share more about themselves with others, and as a result, users will share so much about themselves with others, (who they are, their interests, behavior, location) that they will become victims of crimes like rape, murder or even hate crimes and genocide.

This sounds outlandish, of not even a little silly. Surely, our acculturation with Facebook and the way we use it will evolve over time to protect our selves from this kind of thing from happening.