The text is simply typed on the page. Then some code parses it.
You could write code to generate the text as well, once you've defined a text format. I think XML would probably be a good idea, but I just used a fairly simple [MasterName] then line-by-line Prop=Val format, with a special case for Text.
I thought I'd throw the video up there, just to figure out how to do videos, polls, and to see if people absolutely freak out and go wild over this, or if it is just mildly interesting. Let's wait and see!