I have written an introduction article to Pd in a magazine scheduled to be out on May 17. Unfortunately the magazine is written in Japanese and is mainly circulated in Japan.
http://gihyo.jp/magazine/SD/archive/2008/200806
The index of this issue approximately reads,
..which describes the main range of readers. Hopefully this will bring in some new users & developers to the community.
I would like to thank again all of those who kindly helped me organize the article, and also the entire community.
-- David Shimamoto