After connecting an USB drive, the device notifier pops up. It is possible to mount the device by clicking on the downward triangle on the right of the device's name. It then is mounted. However, this icon does not change to the "mounted" state (which would be the icon to eject the device). There thus is no visual feedback and the indicated state is wrong. The opposite works: When a drive is ejected the icon changes to the "unmounted" state.
Cannot reproduce
I'm sorry, it actually works. I realized this only when preparing a screen cast. The reason I did not see that is that at least on my machine it takes several seconds for the icon to change. It seems that by then I always had left the notifier window and closed it by continuing to work in another area of the desktop, which had closed the notifier window. Some kind of more immediate visual feedback would be great that animates that the device actually is being mounted.
> Some kind of more immediate visual feedback would be great that animates that the device actually is being mounted. Could you file a new bug to track that request?