I'm not used to Apple's stuff at all, and still think that iTunes is absolutely easy to use. Most every function can be accomplished with a click or two, or drag-and-drop. Redesigning the thing completely for Windows won't and shouldn't happen. They didn't do it with Quicktime, and no one complains about THAT program (at least, not its interface.)
iTunes is great. I'd rather use Winamp, but that's because I've been using it for 6 years: I'm under no illusions that Winamp is easier to use than iTunes.
Mind you, given the simple functionality of the playback controls in the Quicktime player, Apple didn't need to drastically change to look and feel to accommodate Windows users.