Sorry, this is not how a bug report should look like. A proper description is mandatory.

Apologies, I referenced the wrong bug. It should have been bug 687658.

Please attach the actual bug report for NetworkManager with all those „this is what it does“, „this is what we expect“ and so on. Then the bug might make enough sense to be reopen. Bug reports in form of links to other bugs are just ridiculous.

When I user switch to another account I am confronted with a stream of "Network connected" "Network disconnected" notifications that are obsolete. They were triggered at some time in the past.

1. We probably shouldn't send such notifications in the first place
2. We shouldn't send those notifications when the user session isn't active
3. We should only have one notification id that is replaced/updated instead of sending new ones
4. We should recall the notification when it is obsolete.

NetworkManager daemon doesn't send any notifications itself. The clients do.

So, it would be helpful if you can state what client do you use so that the bug can be assigned to the right component and analyzed.

Is it gnome-shell network indicator or nm-applet? Grepping "Network
connected", "Network disconnected" won't show any occurrence.

It's nm-applet that shows those notifications.
gnome-shell only has one "activation failed" (and it goes away as soon as the device is connected again).

so, this will be fixed by us not running nm-applet anymore, I assume ?

The applet shouldn't send those notifications anymore (when the shell is running) since http://git.gnome.org/browse/network-manager-applet/commit/?id=05f975d04f47117762b3eddbd80d8e3eb173252d