I posted the Boston Review story Why I Was Maced at the Wall Street Protests by Jeanne Mansfield to my Facebook wall, and it faithfully appeared ("via Links") on my wall. When my friends saw the update, however, they did not get the link. So I posted it again, and the same thing happened. And I posted the URL in a comment, and the comment disappeared. So then I posted the URL with spaces in it in another comment, and the comment did not disappear. Facebook is deliberately filtering comments containing the URL for the story.