It’s been 4 months since I started to use Fedora 15 with Gnome 3 at my job.
I don’t like both Fedora or Gnome 3 (I’m a Ubuntu / Gnome 2 die-hard fan) but the most annoying bug I’ve found was to remove icons from the upper panel, once put, never removed.
I finally got it.
1) Turn off both NumLock and CapsLock;
2) Place cursor over the icon you want to remove;
3) Press Alt + Right Click;
4) Voilá! You’ll see the options Move and Remove from Panel.
Hope this can be useful.