I am obviously a sucka for lists, there's one with 400+ links. I am doing everything humanly possible to try, review (reviews are on the way) and categorize the gazillion startups and old hags alike. I have updated the so called complete list with some cool thumbs (check it out).
B. Berendt, N. Glance, and A. Hotho (Eds.) Workshop at 18th Europ. Conf. on Machine Learning (ECML'08) / 11th Europ. Conf. on Principles and Practice of Knowledge Discovery in Databases (PKDD'08), (2008)
B. Krause, R. Jäschke, A. Hotho, and G. Stumme. HT '08: Proceedings of the nineteenth ACM conference on Hypertext and hypermedia, page 157--166. New York, NY, USA, ACM, (2008)