The SCOT(Social Semantic Cloud Of Tags) ontology is to semantically represent the structure and semantics of a collection of tags and to represent social networks among users based on the tags.
On the “social web” or “web2.0″, where user participation is entirely voluntarily, User Motivation has been identified as a key factor in the mechanisms contributing to the success of tagging systems. Web researchers are trying to identify the reasons why tagging systems work for a couple of years now, evident in, for example, the organization of a panel at CHI 2006 and a number of conferences and workshops on this topic.
Daniela Barbosa, who is the business development manager for Synaptica at Dow Jones Client Solutions has written a fabulous eBook explaining how to mix taxonomies built by professionals and folksonomies, which let users tag content as they see fit