Charlie Stross on fine form:

"[I]f you sign up for Klout you are coming down with the internet equivalent of herpes. Worse, you risk infecting all your friends. Klout's business model is flat-out illegal in the UK (and, I believe, throughout the EU) and if you have an account with them I would strongly advise you to delete it and opt out."

http://www.antipope.org/charlie/blog-static/2011/11/evil-social-networks.html