I think what you want is the way gnome-shell does it.
it also keeps a list of past notifications you might have missed.
> Date: Wed, 13 Jun 2012 14:53:35 +0430
> From: nava.azhdari@xxxxxxxx
> To: unity-design@xxxxxxxxxxxxxxxxxxx
> Subject: [Unity-design] Improving Me Menu + Faster Reply With Mock up
>
> I think Me Menu (Message indicator) can act better.
> I think when it goes blue (when user received a message or mail) it can
> have 2 click event:
> With Left Mouse button Show that message and Let user to quick reply.
> (Just For the First Time Click) (Image 2)
> With Right Mouse button Show Me menu (Like Now in 12.04).
>
> Also It has A Event "Click to Show Latest" , When user Click on it,
> indicator will show latest messages. (Image 3)
>
> i Made a simple mock up:
> http://imgur.com/a/8Ea3v
>
> Thanks
> Nava
>
>
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