Since i updated from Lion to Mountain Lion, i noticed that i am missing the mirror display option is missing in the "screen display" option located at the menu bar. I used this option a lot in Lion, because i work on a MacBook Pro 13.3 inch and have two screens a Dell and a Samsung 24 inch connected depending on the location where i work.
The reason why i used this function a lot is that when i connect my macbook to a different screen that screen will become primary and the MacBook secondary. When i wanted to disconnect the screen i choose to mirror (through the menu bar) so that i immediately had the primary screen on my macbook back. Otherwise i was missing the menu bar on my MacBook. This worked great, because i often needed to take my MacBook away for a moment and connecting back to the display was easy this way.
The new OS got a great feature implemented and that is airplay, but with this feature i really miss the option of choosing mirror on/off. Right nog i need to take multiple steps to turn on/off mirroring. especially on a common day i have to do this like 10 times and with the former OS this was just one click. So my question is if there is a way to get this option back in the menu bar?
Ps. It is called "show displays in menu bar" option in Lion.
option-brightness: Display Preference Pane
command-decrease-brightness: Change display mode (only on revised fn keyboard layout on Alu. keyboards, newer MBP/MBs?
Apart from that, you've gotta go into the display preferences. It's really annoying, I know.