I think the idea behind Libraries is a good one, but it will take some getting used to

Instead of having a "My Documents" folder, there are now a collection of meta-folders called libraries.
Take for example the new Music library - instead of having a single folder full of music in one location (like in XP/Vista), your Music library can contain links to locations anywhere on your PC that contain music. It's a handy way of organising your files, but you can also use it in a similar way to the old folder system if you want.