• The system could have a better understanding of what it finds. For example, a system that could not only recognize words in a Web page but also "understand" the meanings of those words could be quite useful. Unfortunately, the complete understanding problem is AI-hard. On the other hand, some qualities of partial understanding might prove useful.
• The system could have a better understanding of the user's intent. This might come about either through a more thorough and explicit conversation about what the user is looking for (both in general and in particular) or, more subtly, by closer observation of the user's behavior.
• The system could do a better job of applying the "wisdom of others," for example, by understanding pages' structural relationships, taking account of explicit recommendations, recognizing clues in user behaviors, and gauging the trustworthiness of such signals. Think of HITS and PageRank as first steps in this direction, and emergence of sites such as digg ( www.digg.com, user-recommended news), stumbleupon ( www.stumbleupon.com/, shared recommendations about Web sites), and del.icio.us ( http://del.icio.us, social bookmarking), as well as techniques such as photo-labeling games (such as Luis von Ahn's ESP Game, www.espgame.org, in which players try to find matching labels for pictures) as early steps in this direction.