Special track on Engineering Large-Scale Distributed Systems: editorial message

Social phenomena like YouTube and Flickr are incontrovertible evidence of users' migration to a new Web overwhelmed by multimedia. In fact, images, videos, music, and other kinds of multimedia objects today constitute about 99% of the Web. Nonetheless, users' chances of a successful search in such a large portion of information are not proportionally supported. Web search is dominated by giants like Google, Yahoo! and Microsoft that exploit centralized text-only indices enriched by an endless toolbox of smart ranking algorithms. Their interest in riding this new tide is witnessed by the acquisition of both Flickr and YouTube. On the other hand, content-based search for image, music and videos has been deeply studied in the last years but it is not yet adopted by the industry because of its cost.