Scott Schiller, the author of the tutorial mentioned above, sent me this:
This is interesting stuff, I had no idea there was a Google Sketchup community etc. For animations and so on in JS, I might consider looking at some of the modern javascript libraries like Yahoo! User Interface, http://developer.yahoo.com/yui/ or JQuery, http://jquery.com/ which have useful animation components that allow you to easily create and run arbitrary tweened animations on various properties of HTML elements.
I'm looking into his suggestions; if useful I will post some example videos.
Chris