One important point I think is to look at social networking not as a single target or market any longer; social networking properties are evolving into differing although occasionally overlapping categories that can be looked at independently as well:

* Traditional Social Networks/Walled Gardens- FaceBook, LinkedIn, and to some degree now MySpace, have focused on establishing online relationships between individuals with some degree of established relationships in other channels, or in the real world. They assume a desire to establish a trusted relationship where some level of interpersonal, not topic specific, communication is going to take place. FaceBook profiles for the most part have evolved to be more personal. LinkedIn profiles are purely business focused. This type of contextual segmentation, and the ability to keep access to this information invite-only,  is increasingly become more and more important in an era where potential employers Google candidates. These platforms are also more actively attempting to limit the ability of those with whom you have no interest in associating with invite-spam members, with varying degrees of success; also, few if any attempts are made to encourage those that don’t have any interest or connection with an individual at some level to network, except in very limited contexts - i.e. artist’s pages on MySpace. This makes them great places to connect with those you know or know of, but not very effective in connecting to people purely based on interest for the most part.

* Interest-Based Collaborations/Depersonalized Spaces - Increasingly, individuals have a need to interact with individuals in a similar manner to traditional social networks, but purely based on shared or common interest or affinity. These individuals would love to be able to find those with similar interests, connect with them, ask or answer questions, but not allow them necessarily to enter into directly, personal communications or the implicit “circles of trust” that other social networking platforms have become.

There has been a rise in the extremely vertical or interest-focused social network, but they present the user with a real conundrum - how much time and effort do you put into creating yet another profile on yet another social network site? There needs to be a clear value exchange or tipping point to drive those registrations, or else interactions remain brief and mostly anonymous.

* Social Platform Aggregation/Profile Directories - Several startups are now targeting the fragmented social networking space by creating aggregation platforms that will essentially catalog a member’s identify or personalized space across a series of popular, or not so popular, social networking platforms in order to make the process of finding those you know, or want to, online. These startups don’t necessarily focus on finding individuals based on interest or network but on identity, adopting a simple, directory-based approach.

A few startups are now starting to marry the concept of social platform aggregation with this ability to conduct interest-based collaborations while still keeping things depersonalized, and ideally safer, if at least not more controlled.  In the event a trustful relationship does develop, extending the relationship to another social network platform, essentially “up-inviting” someone, allows you to meet individuals you normally wouldn’t, in a controlled setting, to extend your social network based purely on shared interest and affinity. This represents in my mind the “holy grail” or “killer app” in the social networking space at the moment, not just more of the same type of communities and collaboration spaces already out there today.