Dynamic Pages with JavaScript and the DOM

I've been waist-deep in my independent study, and as usual I've been using my current project to explore bits of technology I haven't had an excuse to use before. One such example: JavaScript and the DOM. Coincidentally, Matt asked me a web design question similar to something I built a couple days ago, so I whipped up an example page and figured I'd blog it as well.

The page is an example of a dynamic form that changes depending on the user's input so far. If a user indicates they want to enter a widget unknown to the system, they are provided with a text box for this new widget name. Pretty straightforward, as is the implementation. The driving force behind my page? The DOM method getElementById().

The Mozilla.org website has good DOM reference, and it's been pretty compatible from what I've seen. I'm still new to the scene, though, and not up on all the compatibility issues. More to come later, possibly, as I poke around this topic further.