Peer-to-Peer (P2P) architectures are more and more used in recent content distribution platforms because of their valuable characteristics as scalability, performance, and negligible maintenance and distribution costs. In general, P2P applications allow users to provide preferences that are mainly related to performance, like number of connections and bandwidth limits. As user resources are the wealth of P2P systems, we think it is important to satisfy user preferences in a more meaningful and personalized way. Users should be able to define the kind and quality of peers they prefer to exchange with. In this work, we present What Users Want (WUW), a framework to measure and improve the satisfaction of the users based on personal preferences that reflect their expectations from the P2P system. We then present the design of a distributed P2P service that implements our framework. Experimental results, obtained with a prototype running on top of BitTorrent, show improvement of user satisfaction and the possibility to minimize the impact on the overall performance of the content distribution.