A new analysis of data from del.ici.ous shows that, while the number of tags grows roughly in proportion to the growth of content, users can unwittingly provide bridges between networks of seemingly unrelated concepts.
N. Nakashole, G. Weikum, and F. Suchanek. Proceedings of the 2012 Joint Conference on Empirical Methods in Natural Language Processing and Computational Natural Language Learning, page 1135--1145. Stroudsburg, PA, USA, Association for Computational Linguistics, (2012)
O. Medelyan, C. Legg, D. Milne, and I. Witten. (2008)cite arxiv:0809.4530
Comment: An extensive survey of re-using information in Wikipedia in natural
language processing, information retreival and extraction and ontology
building. submitted.