If you attempt to start any GTK2 app the following will be output to stdout: Gtk-Message: Failed to load module "pk-gtk-module"
Over the course of several Fedora releases there has been a back[1] and forth[2] shift on dependencies on PackageKit-gtk{3}-module. Fedora 17 has removed PackageKit-gtk-module so now there is no easy work around.
The problem stems from /usr/lib{64}/gnome-settings-daemon-3.0/gtk-modules/pk-gtk-module.desktop declaring pk-gtk-module a loadable GTK module.
Could the PackageKit-gtk3-module package be updated to not have GTK2 apps looking for a non-existant module?
[1] https://bugzilla.redhat.com/show_bug.cgi?id=476066 [2] https://bugzilla.redhat.com/show_bug.cgi?id=643129