This is what liberating content is all about. Antony makes a good point about the advantage of not being a not-for-profit in doing this. This is all about the Guardian realising that the action doesn't take place around its site, and that therefore its content must be able move and penetrate the places and networks where the action is happening. A useful lesson for any brand or organisation.
It is interesting that the basic premise of Forrester here is that "experimental" and "sidelines" is somehow not a good thing – whereas actually it is exactly the place social media needs to be. Social media will never be mainstream in the way in which mainstream is currently defined.