Sadly, it's not an incredibly uncommon occurrence for some loser, who has nothing better to do in their life, to create faux Myspace, Facebook or Twitter accounts of public figures. Why in God's name someone would ever waste their own personal time to do this is absolutely beyond me, but it happens. Something else that happens frequently these days: lawsuits.
Thus, it was probably inevitable we'd see the two happenstances collide. Recently, the sports world helped make it happen. Tony La Russa, the revolutionary manager of the St. Louis Cardinals, is suing Twitter because some low-life started a Tony La Russa Twitter page. His grounds are on trademark infringement and "dilution, cybersquatting, and misappropriation of name and likeness."
This is not the first lawsuit involving Twitter -- you can always count on Courtney Love, right? -- but it is the first one (at least that I could find) in which a public figure is suing due to someone else pretending to be him/her. Twitter removed the fake La Russa page just hours after the lawsuit was filed, so we can't see what was being posted there, but the lawsuit alleges that there were Cardinals-related updates sometimes containing vulgarity.
A question raised from this is how Twitter -- and other sites susceptible to impostors -- should be policing their memberships. When everything is done online and users are allowed to fill in their own personal information, how can anyone really be sure who is real and who is a fraud?
As for La Russa, it's easy to say something like "lighten up," but would you really want someone pretending to be you and posting things you have never or would never say? I am firmly in his corner on this one -- if for no other reason than to punish people for having no lives and creating fake pages.
This broad issue will need to be addressed legally by higher courts at some point. Web sites like Twitter would have to spend tons more time and money to background check every single page owner's validity, so it's not really in their best interests to do much more than delete every page that they find out is fake at a later date. They could also argue that their terms of service cover impostors and these fake-posters aren't making any money off the likeness of the public figures.
Some individual public figures can stake a legitimate claim that better monitoring than simple "terms of service" needs to be done at the creation stage to ensure accuracy and protect against their individual freedoms being violated before the fake pages are removed.
Maybe La Russa is the man to get the ball rolling. After all, he is the guy who changed the face of baseball by batting his pitcher eighth.