Comment 5 for bug 431055

The application that is responsible for removing/adding volumes from varios places in gnome is the

/usr/lib/gvfs/gvfs-gdu-volume-monitor

It sends via dbus all noticications, it removes CDROM from computer:// after I insert it
just launch the dbus-monitor, and you see

This thing also appears to mount the devices (at least it tells everybody it did)

This application probably talks to devicekit-disks (stopping it disabled all disk hotplug features)
So hal is already heavily deprecated