I hope I'm not unfounded in saying that there seems to be a trend developing where we're trying to ply out of CSS novel and interesting ways to define the behavior of a page. But doesn't that parallel the issues surrounding visually oriented markup in HTML (i.e. defining the font, background color, etc.)? HTML is for structure, CSS for presentation, and Javascript for behavior, no?

Apart from my concern, the results are impressive as well as appealing.