Power laws and podcasting
A power law is a distribution law where the distribution of values for any ranked order of values n, is of the order 1/n, e.g. the second postion node has a value of 1/2 of the first, the number three has 1/3 the value of the first, and number ten has 1/10 the value. The important feature of this distribution, in comparison to the more familar standard deviation, is the vast bulk of values is concentrated in the few top-scorers. Blog site popularity, for example, is dominated by a tiny number of popular bloggers. Here's an article at social twister which applies this concept to the nascent world of podcasting.