How timely, I just heard the term "power law" for the first time in reading Robb's book, striking my interest in it (I'm busy finally reading up on networks now b/c of the book). Now I learn a lot more about power laws through Hagel. Hagel's push-pull paper is eye-opening too, he has to be the most consistently thoughtful blogger you link to. Thank you for bringing it to my attention.
I first heard about powers laws from Von when his interests shifted from particle research to networks and the kind of cross-disciplinary research his students are doing ( he usually has semi-finalists and finalists in the Intel and Siemens competition)
Hagel's very thoughtful - so much so I don't mind his slow rate of posting.