A number of system-modal dialogs have been converted to 'shell optics' in 3.0: the 'Alt-F2' run dialog, the gnome-session logout/shutdown dialogs, PolicyKit dialogs. There are more dialogs that fall into the same category and will benefit from similar treatment: keyring dialogs, NetworkManager password dialogs, etc. Here are the existing designs for system dialogs: GnomeShell/Design/Whiteboards/AuthorizationDialog, GnomeShell/Design/Whiteboards/SystemStopRestart, GnomeShell/Design/Whiteboards/SessionLogout, GnomeShell/Design/Whiteboards/SystemDialogs.
Somewhat related are device hotplug notifications, see Design/Whiteboards/Hotplug
The work for gnome-keyring is tracked in 652459.
For the gnome-keyring part, Steph Walter
For the device hotplug part, Cosimo Cecchi
For the NetworkManager part, Giovanni Campagna
gnome-shell team, designers, NetworkManager
Keyring: Work-in-progress patches for gnome-keyring exist.
Design bug 656956
DBus API spec'd out, and started in on implementation. 656954
Support for secret exchange between processes. 656955
Clutter patched to support secure prompting (non-blocker) 652653
Device Hotplug: is pretty complete (in patches), see Cosimos blog.
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