Hi pls check a news report here http://www.legalday.com/commentaries/LawNow/Facebook_Firsht_libel_defamatory_postings.html It is about, how somebody registered a name on facebook, to defame. Its not only facebook, in twitter also, anybody can register a username, in order to defame. What is the protection in such a case? (apart from taking to court), Lets say somebody using my real name to create another twitter account and posts spam content, then twitter locks the account because of that, now the real me want to use that name in twitter it is "account suspended" and it wont allow to be registered again. So a vindictive persons are able to effectively lock out a person from ever using his or her own name in twitter again.