|That send button can be dangerous!|
In a recent New York case, a court took away custody of a Mother's children as a direct result of her Facebook postings. You can read the case here.
Rule to live by: DO NOT POST AT ALL. If you must post, and for some reason, people cannot stay away from the internet - even if their case depends on it, only press send if what you post is something that you would want the judge and your grandmother to read. Of course, this does not mean to use Facebook as your own personal public relations site -- that can also backfire and you can be viewed as someone oblivious to the privacy concerns of children and your family.