Government pays agency to astroturf positivity on the Olympics?

Whatever your view of the 2012 London Olympics, would it be right for the delivery team for the event to be paying a PR company to jump around the Internet leaving astroturfing comments about the Olympics being wonderful, and the preparations being perfect? I ask, because that, at least on face value seems to be what is happening.

Phil Taylor, a councillor in Ealing, recently found a comment had been left on an old post he did about the cost of the Olympic logo - that's the logo that looks like Lisa Simpson performing fellatio. The comment said,

Come on! It is not so bad! I am proud and excited about the Olympics coming to London. I found a good post about London Olympics. It looks like we are preparing well for this event! Can’t wait!

The IP address of the commenter traced back to a PR company called TradeDoubler or specialise in "performance-based digital marketing". TradeDoubler also happen to have purchased the company that looks after "VisitBritain", and agency of the Department for Culture, Media and Sport, which funnily enough is where the link in the comment went too.

Has anyone else found that posts badmouthing the Olympics have been astroturfed in this way?
Hat Tip: Phil Taylor