I found a "solution" that might be helpful to those fixing the bugs. On my Quantal system I downloaded the "ambiance-colors" theme, then the latest Ubuntu Tweak (0.73, testing). I used Ubuntu Tweak to try to apply the ambiance-blue theme; the window theme applied just fine, but not the Gtk theme, so I used the reset button to undo the change to the Gtk theme. After that, all the other menus mentioned in this bug, such as the indicator menus in the panel, worked properly. This includes the Nautilus menus. So it appears that there is something to messing with the Gtk theme and resetting it that fixes the problem.
I found a "solution" that might be helpful to those fixing the bugs. On my Quantal system I downloaded the "ambiance-colors" theme, then the latest Ubuntu Tweak (0.73, testing). I used Ubuntu Tweak to try to apply the ambiance-blue theme; the window theme applied just fine, but not the Gtk theme, so I used the reset button to undo the change to the Gtk theme. After that, all the other menus mentioned in this bug, such as the indicator menus in the panel, worked properly. This includes the Nautilus menus. So it appears that there is something to messing with the Gtk theme and resetting it that fixes the problem.