In this paper we present a second generation URL monitoring tool which enables the collaborative evaluation of URL content changes. In our implementation, a document monitoring agent works alongside a recommender system. Using information provided by the monitoring agent, the collaborative system alerts users when documents they are monitoring have changed. The monitoring agent provides automatic evaluation of the nature of the change. Users, however, add subjective evaluations; one user's

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... t informs all others monitoring the same URL. Based on these subjective evaluations, the collaborative system can filter the changed URLs, providing customized notifications for each user based on individual preferences. In this paper, we describe the implemented system and usage results.