Comment 3 for bug 146946

I can confirm the bugreport.
Randomly, and without an apparent cause, gnome-settings-daemon does not start, and it shows the standard theme / icons, the mounted drives not appearing on the desktop or under the 'places' menu, with a window telling me g-s-d did not start. As LCID Fire said, starting it manually does work, and restarting x.org does resolve everything. That problem was really frequent until a couple of weeks ago, but it still continue to appear.
With the manual start, I can tell that's not the known and resolved situation of g-s-d not starting at all, as it starts.
I am at your disposal for every information you could need.