Another interesting ReadWriteWeb article, this time on how life is shaking out in the social bookmarking world. The article has a number of interesting types of analysis, but the main focus is on user-ship. On this dimensions, del.icio.us dominate, with more than 10x more users than the next best (Magnolia).
My predictions is that there should be a moderate vortex effect in social bookmarking, with benefits to the category leader because of the greater volume of other users creating value by adding their bookmarks. On the other hand, in the absence of true personalization in this category, the vortex should be limited, since above a critical mass the additional users add more noise than additional value. In fact, we should expect to see a number of secondary social bookmarking sites spring up with the goal of attracting a clientele that shares similar tastes. In a sense, this will let people find their own "neighborhoods" of others with whom to share bookmarks, rather than sharing with the unwashed masses. Unlike with automated personalization, these neighborhoods will most easily form when they are structured around easy-to-understand syntactic categories, so the usual suspects — religion, politics, and sex — seem most likely as the fracture points.
No, it probably is not coincidence that these are the traditional "off-limits" topics for casual conversation. These are topics about which people prefer to talk to people with whom they agree.
I’d personally rather see a more personalized approach from one of the top social bookmarking sites. Such an approach might lead to a much stronger vortex effect, and the opportunity to dominate the category.