Re: Walk before you can Run
Facebooks is trying to avoid to build the network, it's trying to piggyback on someone else but lure traffic only to its sites. Once users are accustomed to a certain definition of the "Internet", they won't look elsewhere easily - especially if they have to pay for it.
I've seen it already in other sectors (i.e. TV broadcasts, newspapers web sites) - once users are used to a free service, no matter how bad it is, they won't switch to paid services easily (even if they can afford them without much trouble), even if the services has far better quality - thus if you control what the free services offer, you control what a lot of people see (and think).