[Hauken]

So on my ATV2 movies, tv shows etc are scanned and scraped no problem. Folder art and all,

My music is sorted by iTunes, so folders named after artist with files inside. If I turn off library mode, highlight a folder and say scan to library it'll scan that one, get fanart, album art etc etc just fine, but it won't scan in all my music?

[procrastinator]

If you're using the last official release then it could be related to this issue:
http://forum.xbmc.org/showthread.php?tid=92934
where music scanning stalls on certain .m4a files. I believe this is fixed in the latest nightlies.

If it's not scanning at all then I'm not sure what's happening. You need to give more info to get a accurate response. Provide a debug log. See this thread for info on how to post about problems properly, and how to get your debug log off the Apple TV:
http://forum.xbmc.org/showthread.php?tid=92480

[olympia]

To automatically download metadata and artwork during library updates, you have to turn on downloading of additional information in music settings.

If you already scanned in your music, then select 'query info for all artists' from the context menu of one of your artists and select 'query info for all albums' from the context menu of one of your albums.