I’ll have to politely disagree that there’s not a social network out there for the “physiological” needs of human beings. Hint: it’s a multi-billion dollar industry that is in most cases the first to innovate technologies and sets the trend for most other industries and no, it’s not Aerospace.
As the “social” movement rewires the global [digital] landscape, expect to see more interactive and innovative ways to fulfill oneself on the web. Also expect to see more (smart) brands reevaluating how they interact with their consumers (e.g. “Customers are not a subject of a sale but an object of an experience”). Marketers, use Maslow’s original hierarchy as cheat-sheet to develop your content but never forget that yesterday’s Myspace is today’s Facebook, etc.