The 2nd International Workshop on Information Heterogeneity and Fusion in Recommender Systems (HetRec 2011, http://ir.ii.uam.es/hetrec2011) has released datasets from Delicious, Last.fm Web 2.0, MovieLens, IMDb, and Rotten Tomatoes. These datasets contain social networking, tagging, and resource consuming (Web page bookmarking and music artist listening) information from sets of around 2,000 users.
The datasets were generated by the Information Retrieval Group at Universidad Autónoma de Madrid (http://ir.ii.uam.es). Before using these datasets, please review the README files for the usage license and other details.
105,000 bookmarks from 1867 users.
92,800 artist listening records from 1892 users.
MovieLens + IMDb/Rotten Tomatoes
86,000 ratings from 2113 users.