Summary
The thing that TV networks, radio, print, etc did to build was create compelling content. Content that drives interest from customers. Networking sites, while are great places for connectivity and community, they lack the drive and resources to be true media giants. This is where Yahoo! or other portals with media assets could bridge the gap for customers. Socializing and entertaining - that keeps people around for advertisers. And developing the best ways to integrate advertisers into that hybrid social/entertaining experience is where brands can deliver the most effective messaging.
Analysis
Facebook needs to be bought out because Facebook can't build experiences into their site. Socialization and community are there, but entertainment is not. It's the tentpole entertainment experiences that will drive the user base to interact with not only the sites features, but the advertising that supports them.
Overall the more networking sites the more segmented the experiences get. Niche networking versus mass networking it will all evolve around the ability of these sites to generate entertainment for the consumers. The easiest way for these sites to gain access to development resources and entertainment is to be bought by the company best positioned to introduce advertisers to the experiences of the sites.
I believe that Yahoo! is that site.
