The National Institute of Standards and Technology (NIST) has done us all a favor. They posted a working definition of cloud computing that serves as a foundation for its upcoming publication on the topic. Computer scientists at NIST developed this draft definition in collaboration with industry and government.
And, it's pretty good. If you were looking for a decent definition or to get a better grasp on what-the-cloud-will-mean-to-you, check it out.
WIIFM - what's in it for me
RT from @MikeNelson