Urban road authorities mainly rely on traffic demand management strategies to operate the road networks they are in charge of. They used to be the only ones able to gather traffic data, and thus to have an extensive knowledge of their network. Today’s widespread use of GPS and other mobile devices (held by drivers and/or embedded into the vehicles) means that new actors are now able to build a knowledge of the network, and therefore held the necessary material to make decisions as to which routes their users should use. Hence, traffic management is becoming an intricate and complex system where public authorities, private companies and user communities are intertwined, with different aims. The paper thus addresses the following: do centralized traffic information systems still have a meaning nowadays, or in the forthcoming years? To begin with, the paper provides a comparative analysis of centralized traffic management policies in the cities of London and Paris. This is followed by a short review of new players in the traffic information and data collection market. Finally, a traffic dynamic macroscopic model is proposed in order to study how different classes of users interact on current road networks, each class being characterized by the type and level of information it has access to.