In Adobe Photoshop CS5.5 / CS6, is there a keyboard shortcut to make a new frame using the animation window and timeline?
I make a lot of gif animations and would like to reduce mouse movement for productivity.
No. But, you can make a hotkey for it.
From top menu:
( Make sure to listen to photoshop when it warns you if the inserted hotkey combination would override any existing ones. You can try to use Ctrl, Shift+Alt to make sure that it doesn't happen. )