The design of tourism products is changing due to factors such as the growing importance of the Internet and the ability of tourists to be involved in the production of their own products/experiences, (namely the emergence of the 'prosumer'). This paper reports a study into the responses of Tour Operators and On-line Travel Agencies to the evolution of the tourism sector. The case-study analyzes the use of marketing mix variables for outbound tourists from the United States booking tours to Italy. A comparison between operators and the five main on-line travel agencies is then made. The purpose of the paper is to demonstrate an ongoing repositioning of these tourism players along the long-tail theory curve and a reversal of the Tour Operator's role, from that of a general mass market orientation to the supply of a niche market demand by promoting customized travel packages based on specific requirements. Implications of this process for the marketing of destinations and SMEs are discussed in the final part of the paper.