I am running on Fedora 15 x86_64, thunar-volman version 0.6.0-2 on a Dell XFR D630 laptop.

Here is what I have done:
1. Check "Enable Volume Management"
2. Check every check box under removable storage including "Mount removable drives when hot-plugged", "Mount removable media when inserted", "Browse removable media when inserted", "Auto-run programs on new drives and media", "Auto-open files on new drives and media".
3. Check "Play video CDs and DVDs when inserted.  Saved command as just "/usr/bin/gedit"
4. When a DVD movie (not copy protected) is inserted, an icon appears on screen saying "DVD Video Recording" and hovering over that icon says "Removable Volume Mounted at /media/DVD Video Recording"

/usr/bin/gedit may launch, or it may not.  In playing with this, many times the DVD would not even be mounted, and as I was writing this report it suddenly started to get mounted consistently so I had to rewrite some things.

I realize there is not much to go off of here, but I'm willing to provide any logs or perform any debugging that could assist you.