Here is a detailed summary from a student.
The main points I would like you to remember are the democratizing potential of social tagging and folksonomies. Since labeling and classifying can have a foundational impact on how we relate to the world, it is very important that more people have access to creating structure and organizing the world. The world according to Dewey looks very different than the worlds according to a Buddhist monk, for example. Now we can, in theory, have access to both worldviews. In practice, issues of access, of cultural domination, of being unable to see outside the constraints of the mainstream worldview, threaten the democratizing promise of social tagging.