Previous heroic massive open online course (MOOC) efforts such as Khan Academy, MITx, and Udacity have been limited by their inability to embrace a full range of the types of courses offered on a traditional campus. Coursera is attempting to bridge that gap by offering classes from four major universities; Stanford, Princeton, the University of Pennsylvania, and the University of Michigan, in more than three dozen subjects.
http://www.onlineuniversities.com/blog/2012/04/coursera-the-latest-education-hero/