XML, XSL and XHTML, oh my!

I've moved into the next stage of my project at work and am now up to my eyeballs in XML and XSL. So far I like what I see. I've already had to get "creative" to work a few things out and it's pretty fun seeing these bits come together. I'm sure there are plenty of ways for me to improve what I've done; for now, I just want to get the logic working, and then I'll clean up once I have a good starting point. This is my first foray into the XML/XSL world and there's nothing like a trial by fire to learn things fast.

OK, so I don't really have anything to say about XHTML in this particular post. I can say, however, that I have at least one page of my application almost entirely code-generated (and not from XML/XSL) and validating perfectly to HTML 4.01 Transitional. I'm not going to be overly picky about which DTD I validate to - I'm more concerned that I do validate.