It's definitely not useful, and it's not very dynamic... it sort of sticks at the same level most of the time. Also, don't turn on the screen visualizer. Seizure.
Thanks for that link, quite fun.
edit: There is a glitch though. I've found that changing tracks in iTunes even with the visualizer off, turns off the backlight. Removing it from the plug-ins folder and relaunching iTunes fixed this... Menuet also crashed while running it, but I'm not sure that's related...