iTunes has set the bar and you can see its design spilled over into software of all kinds on every platform.

Other music management applications tend to use it as a blueprint for their own designs as well. Songbird, despite what its creators claim (which is that common interface elements are borrowed because they're "best of breed"), isn't much more than an iTunes clone built on XUL.

What aspects of iTunes don't you like? Keep in mind that while I've installed the Windows version in the past, I really only ever use the Mac OS version. I also use it only for management, not for playback, and not for file organization. iTunes has only been a solid product since version 7 and the introduction of Album-based views.