Zach Holman notes that iTunes 9 incorporates a somewhat hidden feature that allows you to organize your media library into logical folders (Music, Movies, TV, Applications, Podcasts). Further, once you’ve upgraded, iTunes creates an “Automatically Add to iTunes” folder that permits drag and drop installation of media to the iTunes library. This could potentially be quite useful, as you would then assign it as your download folder for media and not have to think twice about organization.

iTunes Media Organization, Zach Holman (via Daring Fireball)