I have read that the Netflix engine is quite superior, but I’m not sure exactly how one judges that. They do spend a great deal of time and money refining it constantly, and recently had a contest where they paid software engineers a huge prize for increasing its accuracy.
” I use my extensive and growing knowledge to give recommendations and help you discover new music, movies and books, based on what you already like. Some call me a discovery engine or a recommendation system, but I prefer to simply be called TasteKid :)”