In this website you can find information about folksonomies, their strenghts and weaknesses, and Sem4Tags an approach to improve multilingual folksonomies using semantic web techniques. In addition, there is information about the developed demo software to associate tags with semantic entities.
A. Hotho, R. Jäschke, C. Schmitz, und G. Stumme. Informatik 2006 -- Informatik für Menschen. Band 2, Volume P-94 von Lecture Notes in Informatics, Bonn, Gesellschaft für Informatik, (Oktober 2006)Proc. Workshop on Applications of Semantic Technologies, Informatik 2006.