Unable to eliminate the popup box that occurs when a new selection is played

I just upgraded to Ubuntu 12.04. Each time a new selection is played by rhythmbox, a popup window displays info on the new selection for 10 seconds or so and then disappears. I wish to eliminate this popup.

The help docs tell me that:
The Notification Area is a GNOME feature that adds a small icon to the panel while the program is running; this allows you to control Rhythmbox Music Player from your tray, and receive information when the Rhythmbox Music Player interface is not visible.
AND
I can click on this icon to deselect "Show Notifications".

I find no such icon added to the panel.