Making Money from Social Networks?

In her post On the Monetization of Social Networks, Gladys Priso writes:

"An article on the economics of social networks published by the Economist Online, concludes that “social networking may end up being everywhere, and yet nowhere,” because it is not clear how companies will be able to monetize that pattern of behavior."

Experience suggests
that migrating a free-service to a paid service rarely pays off. The content
would need to be unique in terms of either content, accessibility or
connectivity to like-minded people. LinkedIn appears to provide services that
allow payers to see everything about every LinkedIn member. I happen to know
many people who find that service of great value.

So perhaps the users
continue to get access to social networks for free, but the advertisers,
marketers and recruitment consultants provide the revenue stream for the site
owners. However I do feel that with good brand management the social networking
sites can cultivate the exclusivity effect needed to attract impressionable
cash-rich surfers.