Does your institution have a policy regarding policing online student feedback? There has been a lot of recent comment regarding the UK release of the "Rate Your Lecturer" website. This website allows users to comment on and rate their lecturers. Comments are submitted anonymously.

I do not want to enter the debate on whether this sort of anonymous online reviewing of lecturers is good, bad or indifferent. 

My question is whether your institution has a policy regarding how to deal with demonstrably untrue, insulting or unfairly negative comments about lecturers posted online, and what that policy is.
No policy that I am aware of at any of the four universities and two high schools I've been associated with.  When the sites first appeared in the U.S. about ten years ago, questions came up about whether anything could be done about it, and the institution I was associated with then decided that there wasn't anything legal that could be done.  I believe that libelous material can be appealed directly through some of the websites, but I've never heard of anyone having success with that.

Personally, I love anonymous feedback, and I've had my share of good and bad reviews.  I've tried to use the bad reviews as a means for informing where I can improve, and I've tried to limit my head from getting too big at the good reviews.  Teaching takes a certain amount of thick skin, and sites like these can be a good way to test if you've grown enough of that calloused layer to ward off any long-term effects.