"Crowdsourcing is the act of taking a job traditionally performed by a designated agent (usually an employee) and outsourcing it to an undefined, generally large group of people in the form of an open call." The term has been around for several years and the momentum has been growing. We can now see it in the changes to stock photography, Dell's new release of Ubuntu computers and more.
Jeff Howe's book, Crowdsourcing: Why the Power of the Crowd Is Driving the Future of Business, was released yesterday. It's available at the ususal online sources and probably in a store near you. Yes, there are other books about the wisdom and power of crowds, but Jeff Howe is credited by Wired as identifiying the concept in 2006.
Here's a link to a Jeff Howe trailer about the phenomenon on the crowdsourcing website .