The reason why the Long Tail concept seemed so familiar to me is that I work with the statistical cousin to the marketing term, the Heavy Tail.
The term Heavy Tail is used to describe a dataset that is not "normally" (in the statistical sense; think Bell Curve) distributed. Internet performance data is notoriously heavy-tailed, with a large concentration of datapoints to the left-hand side of the population and a very slow and long/heavy tail trailing out into the nether reaches of "where things go very wrong".
When I gave training classes, I described this (being a Canadian, of course), as the Beaver Effect. If you are as puzzled as some of my seminar participants were, I am not suprised. However, go look at a picture of beaver — none posted here; you know how to use Google.
Huge Body; large tail. The Beaver Effect.
Guess it doesn’t resonate like the Long Tail.