In the age of the Web, social attention and its swift allocation through vast social networks play a central role in the generation, dissemination, and validation of ideas and results within large communities. This growing trend is likely to become dominant because of the ease with which people can now contribute to the global chatter. We're witnessing an inversion of the traditional way in which people have generated and consumed content. From photography to news to encyclopedic knowledge, in a centuries-old pattern, relatively few people and organizations produced content for consumption by everyone else. With the advent of the Web and the ease of migrating content to it, that pattern has reversed. Today, millions of people create content in the form of blogs, wikis, videos, music, and so on, and few can attend to it all. This phenomenon, known as crowdsourcing, is exemplified by Web sites such as Digg, Flickr, YouTube, and Wikipedia, which produce sought-after content rivaling the best published sources without traditional quality filters.