You can completely change the appearance of iTunes 10 by running the application in something called High Contrast Mode, which effectively inverts the list display so that the text is white on black (see the screenshot, it’s a very pronounced change).
To enable High Contrast Mode, enter the following command into the Terminal:
defaults write com.apple.iTunes high-contrast-mode-enable -bool TRUE
You can revert the changes back to the normal iTunes 10 appearance with the following:
defaults write com.apple.iTunes high-contrast-mode-enable -bool FALSE