Interest-Based Social Networks

I read from TechCrunch intriguing article concerning interest based social networks. With the pending IPO of Facebook one might say “social is done,” Facebook is all the social media anyone would ever want or need. With its one billion accounts, "in the solar system of social media, Facebook is the Sun — the gravitational center around which everything social revolves". However users clearly haven’t gotten the memo. Instead, users are rapidly adopting new interest-based social networks such as Pinterest, Instagram, Thumb, and Foodspotting. The article states: "What accounts for the fast growth of these interest-based social networks, and what does it mean for Facebook’s future?

Interest-based social networks have a markedly different focus and approach than Facebook. The Pinterest, Thumb and Foodspottings of the world enable users to focus and organize around their interests first, whereas Facebook focuses on a user’s personal relationships. Facebook offers us a social utility to deepen social connectivity with our existing social graphs, while these new interest-based social networks enable users to express their interests in new, engaging ways and offer authentic, high value connectivity with new people we don’t already know."
Furthermore, "There are opportunities to establish differentiated, sustainable social media brands with large, passionate audiences. Much like the modern day media disrupters (e.g. ESPN or HBO or CNN), these services can establish new social media networks that are differentiated and unique, protecting them from the inevitable concern that they get squashed by Facebook. The traditional “Big 3 networks” (NBC, ABC, and CBS) used to be the only properties that really mattered, similar to how some view Facebook, Twitter and LinkedIn in today’s social media landscape. Emerging networks will be the new media brands and properties that augment social networking and media."