feuerfalke writes "Facebook recently scrambled to fix a security issue with their privacy controls that allowed users to get a peek in to their friends' live chat conversations and pending friend requests. The issue existed with Facebook's privacy feature that allowed users to view their profiles as other users would see it. From the article:
"Link to Original Source
"For a limited period of time, a bug permitted some users' chat messages and pending friend requests to be made visible to their friends by manipulating the 'preview my profile' feature of Facebook privacy settings," Facebook said in a statement.