A few years ago, the operator of RatingZone checked in to the AlexLit-related newsgroup at sff.net, and asserted that he had the collaborative recommender that would kick all others to the curb. Or some such claim. Feedback from the group was swift. Defensive or not, most thought his database of ratable books was too thin. Also, RatingZone only allows ratings of books, so that folks used to making distinctions between the quality of different parts of a book had to figure out how to make an aggregate judgment.
The RatingZone official responded that they were prepared to field most requests for new additions to their title database. The decision to allow only ratings for books instead of stories is probably a user issue: most people would think about the specific items that they could check out or purchase.
So, RatingZone is out there. Besides offering recommendations for books, you can also get recommendations for movies, music (albums only), TV shows, Radio Shows, Magazines (and newspapers), Retailers, Web Sites, Restaurants, and Travel Destinations. It is not clear whether your preferences in one area are used to offer predictions in another, though I suspect not.
All items can be rated on a scale of 1 to 10, and you can use different drill-down browsing methods to find what you want to rate. RatingZone does a halfway decent job of adding new movies, but, since late 2003, has stopped adding items in their other categories. The movie system will offer recommendations pretty quickly, and will make fairly conservative predictions that will hold for a while. This suggests that they only update recommendation lists on an irregular basis, or that new ratings are slow to be coming in. I've found that my top recommendations make for an interesting blend of old and new, obscure and well-known, and provides a good mix of genres. Currently, RatingZone is recommending Pixote.
RatingZone will not give you recommendations on specific items, only generating a recommendation list. I like their movie service and let it influence my viewing choices, but, I cannot recommend any of the other categories because of their decision to neglect those fields.
The system is operated by a marketing consulting firm by the name of MediaChoice. According to a February press release, The "Affinity Analysis" technology behind RatingZone is currently being used to allow casino "gamers" to rate slot machines. MINI-DISCLOSURE: I participated in a study by MediaChoice ostensibly to test the appeal of a mid-profile science fiction novel release, for which I was compensated with two more paperbacks. None of the three books rocked my world, though I am disappointed that no more opportunities like that have cropped up. Its nice to get free things every once in a while.