After 4 years, I finally got sick of GOOM and decided to figure out how to get more visualizers in Totem and Rhythmbox.
Turns out all you need to do is install the libvisual-0.4-plugins package through Synaptic. Piece of cake.
In Gutsy this buys you eight more visualizers, although I was hoping for more than that*. I feel the urge to write a cool visualizer one day, seems like a good weekend project.
* I was hoping that it'd be like installing xscreensaver-gl-extra and xscreensaver-data-extra, where you get a ton of really funky new screensavers.