I still keep my folder structure the way I want it. iTunes oesn't mabage that part if you turn the option to copy songs OFF. So I can still manage stuff IN and OUTSIDE of iTunes.

I now have Album art on nearly every track in my collection and iTunes ability to properly group together Various Artist albums and its sub-sorting capabilities are why I use it. Looking simply at folders you have exactly one view on your tracks. That's not something I want for music. Using Spotlight and smart searches you can somewhat get around this of course, but iTunes as of version 7 does an amazing (and reather quick) job of it.

Hopefully sooner rather than later, I can start using a SqueezeBox 3 and Slimserver as well. Now I just need someone to write a piece of software that lets me use the iTunes UI to control playback from SlimServer. Or a plugin of some kind for SlimServer to make it look like an Airport Express to iTunes.