Hey, The problem is not resolved with the last package of gnome-shell, version 3.8.4-8 .
It seems that the problem is due to an incompatibility between nautilus (current version 3.8.4-2 in testing) and gnome-shell as icons on the desktop are managed by nautilus. I read on a forum that a user has uninstalled nautilus to replace nemo no longer has the problem.
