To clarify the earlier post on notifications on Glacier, here’s a nice, short illustrated version. And a sneak peek at the Gallery app.
For notifications that need user attention (but don’t take the user completely away from the current context), the entire viewport lifts up, uncovering the notification. The user can then dismiss or act on that notification.
For other notifications that aren’t as urgent, the viewport simply shrinks, the notification appears, and disappears after some time.
Quite sleepy as I write this, so maybe I’ll finish it up more tomorrow, when I have time.