Read this. They did not say they were shutting down facebook.
http://www.cnn.com/2009/POLITICS/09/28/facebook.poll/index.html
What they said is someone created a poll asking about if you think Obama should be killed...and the secret service is investigating.
Common sense tells you not to post on Facebook and common sense tells you not to post it here.
I'm sorry you think it's dangerous. And it can be. It's really not a lot different than this forum. And actually Facebook is more private than this.