An anonymous reader told me: "people need an incentive/experience to provide this information for free. They will assume that their friends know - so why should they tell Facebook this information?"
In my previous posting, I showed that skills cannot be faked because they are judged by the rest of the friends. This is nothing but just applying the power of social ties which self-regulates authenticity.
Now, let's go to the next step. I believe that current web ads system is fundamentally flawed. A lot of people produce web content which is then indexed by search engines. When a query about a topic is submitted by a user some relevant content is retrieved and ads are sold together with the results. The engine takes the money and the content producers take no money.
Yes, content producers will receive more traffic and this has certainly an economic value. Anyway, who said that this is the only model we can think of?
Do you have any alternative?