Thanks to all for the kind words. This article actually went up a little bit before it was supposed to, and there should be a revision going up soon with some grammatical fixes and a set of graphics to illustrate parts of it. I'll post a follow-up when that happens in case anyone wants to go and look at the pretty pictures.
While we're on the subject, thanks to everyone who contributed to the many open source projects that we used. We couldn't have done it without you. - Perrin