I just loved it! If itunes had something like that on its visualizations it would allways turned on. Yes it needs a little bit fine tuning... but you're on a good way!
It would also be nice other experiments... perhaps some way to communicate sound trough words in different typefaces and weights.
I've developed during the weekend a quick sound visualizer involving type.
It's still a working progress in need of further improvements.
You can check it at:
http://www.tezzutezzu.com/blog/typography/dancingtype
Let me know what you think!