I agree with the observation Free services devaluation: what’s next? that there needs to be (and will be) great evolution of the social networking business model away from what created FaceBook, MySpace and similar sites.
I disagree, though, with the use of Second Life as an example of a social networking site which does not work because of the model, or because of incongruity between corporate presence and user alienation by corporate presence. The problem with Second Life if the implementation – it is crap.