Online reference managers are extraordinary productivity tools, but it would be a mistake to take this as their primary interest for the academic community. As it is often the case for social software services, online reference managers are becoming power
Real life data needs are never semantically pure. Users need to browse their data in different ways. Hierarchies are too hard to reorganize on a whim. Stuff I need access to DOES NOT HAPPEN TO EQUAL the stuff at the top of the tree: Hierarchies are bad a
You can tag arbitrary content on the web, you can do it in a low-tech way to make it easy for everyone to do...But...How do you find instances that people haven't tagged? Or deal with overlapping meme labels?