I too believe this is a great feature! maybe I didn't explained myself....
I mean... for example... I use a hard disk as a media library.. (since Win98

)... so in XP, I just added the specific music folder to my windows media player and I could manage my whole music folder from there.... Now... In Windows 7, I added the same library I use for XP in the Windows Media Player but I only see the files in the first branch.... (as: G:\Public_Library\Music\song.wma)... my question in more related to the songs in the folders inside "Music".... (as in: G:\Public_Library\Music\Jazz\song_2.wma)... I know I can add them manually one by one... so there's my question mark: ¿Is there a way to include subfolders in a especific folder into the Library?
I know it's kind of boring, but I only remember my dad telling me "it's the small things the ones that make a difference".... Windows 7 ain't small, but so far I don't ever want to go back to XP or Vista....