Brian Dennis does not buy the claim that social software is loosely coupled.
For a half a minute, I’d bought into loose coupling but realized that many of the services cited (Technorati, Flickr) are even more centralized than USENET ever was.
True, Technorati and Flickr and Audioscrobbler and del.icio.us are each centralized services. But each of these services has APIs and/or XML feeds, and these are commonly used to assemble composite services — Flickr photos posted to a 3rd party weblog, a Technorati query showing the conversation around a particular post, an Audioscrobber RSS feed showing a playlist.
The loose coupling is in the combination of tools, not each tool.