On a slightly related application development note, I was glancing at the printout of Jesse's Elements of User Experience document that I keep by my desk, and I realized that a large part of the frustration in creating the application I've been working on the past few months is due to the fact that CSS only describes the "Web as hypertext system" part of the user experience, but is woefully deficient in describing the "Web as software interface" part, except in the most cosmetic and superficial senses. (Yes, I did an all CSS and XHTML application in a production business environment. Love me, I do!)
Whoopsie, actual technical content. Will go back to singing in the shower now. Meanwhile, tell everybody what you think about the web's maturation as an application platform.