In the business world, taking market share from competitors is much more expensive than creating/cultivating a market from scratch. On the Internet, it’s almost impossible. A common phenomenon across the history of the Internet is that the first form of an application that achieves a certain critical mass becomes culturally definitive of that application, creating powerful resistance to even technically superior competition. This is illustrated by how we now commonly use the word ‘google’ as a verb to denote the very concept of web search. Who then can hope to compete with that? The brand defines the whole concept.
Facebook became what it is because of the neglect of the open source software community which tends to be contemptuous of (or at best indifferent to) novice computer users, regarded such uses of the Internet as frivolous, and saw no need for improvement on the concepts of the mailing list and Usenet. The for-profit developers of Facebook, Reddit, Digg, et al recognized the potential market hidden in the novice user frustration with so much of the early Internet and built businesses around that. Now that Facebook has achieved a mass of eyeballs to where it has become the cultural definition of what it does --to the point where quite a few users no longer know the difference between the Internet and Facebook– it’s going to be extremely difficult for an open alternative to achieve any critical mass even if it’s technically superior.
To overcome the hegemony of Facebook requires reimaging the underlying concepts of the social networking/media application to such a degree that you supercede it like the car superseded the horse and carriage and thus re-capture the cultural definition of the application. But what might do that? My bet for this has been the Social-Semantic Networking concept of Netention and what I’ve come to call the Digital Tao, but these are concepts that depend on the future development of Semantic Web technology.