Before the Display preferences were available in the menu bar in OS X, connecting my Mac to an LCD projector was a tedious thing. When it arrived a few OS X versions ago, I showed everyone I worked with how much easier it was to use this, instead of hopping into the System Preferences every time they hooked their Mac up to an external monitor or projector. Then OS X 10.8 Mountain Lion came along and replaced the Displays menubar item with an AirPlay focused one, and I’ve missed the original ever since.
The developers behind third-party app, Display Menu, thought the same thing and fixed things for us all.