The Web 2.0 world is commonplace but the promise of massive scale human computing has barely been exploited. This seminar explores the potential, challenges, and promises for next-generation technologies that can empower humanity to address key problems. Although the read / write world of Web 2.0 is now commonplace - even your parents use Facebook - the promise of massive scale human computing has barely begun to be exploited. New technologies, including the Semantic Web, mobile computing, and open data suggest ways that far more powerful systems than those we have today could be created, empowering humanity to help address some of our key problems. The potential for the sharing of data and knowledge, among willing participants, makes it possible to envision declarative models for creating and evolving new Web technologies that would more open and distributed systems. Further, by explicating the social, not just the technical, protocols, new models of information control that encourage, rather than prohibit, sharing can be explored. In this talk we explore the potential for next-generation social machines, explore some of the challenges, and look at promising technologies for the future.