When using social media sites, many people are quite casual about what they say, often posting material that could be viewed as unpleasant, offensive, or critical of others. Under what circumstances do you think someone could be sued for defamation based on comments made on Twitter or Facebook? For example, consider the case of a Massachusetts woman who sued her friend for posting a message on Twitter stating that she was "crazy," or the health club owner who sued posters who gave his club a one (out of a possible five) star review. Should such postings be actionable as defamation?