In comparison to WinAmp's visualization selection, iTunes is like a desert. There are a few nice ones, but most of them are similar to visuals that WinAmp had 5+ years ago.
But, honestly, how often does the avg user really need them? If I am listenign to music, iTunes is minimized and I am working or doing something on the computer. If I need music while cleaning etc, I use TivoDesktop and play the music off my tivo itself.