Allan Day recently blogged mockups for a possible redesign of the notifications area. This new design still has the notification area appearing from the bottom of the screen, but rather than a horizontal tray of icons, it adds the notifications to a pop-up in the centre of the screen.

message-tray-drawer

This new design allows for a greater amount of detail when glancing at your notifications, rather than just an icon, and the number of unread notifications. The upstream developers seem to be targeting getting this new design implemented for GNOME 3.14, so hopefully we should see this in Fedora 21 Workstation.