I'm using ubuntu 10.04 LTS with Firefly svn-1696 as server and iTunes 10.6 on a Mac as client and the problem still exists.
iTunes waits forever while trying to load music list. It does not stucks with the rotating ball; just hangs indefinitely. The problem is in iTunes because other daap protocol aware application like Banshee and Rhythmbox work flawlessly.
I figured out the way to fixed this. The problem is not with your Firefly Media Server the problem is with iTunes.
Leave your Firefly Media Server alone and edit your iTunes. Please follow instruction on the link I provided below to make iTunes work with Firefly Media Server again. Since, I searched the forum and found no solution for this so I would appreciated anyone who repost this please leave the credit to me. Thanks.