Steve Gibby
Red Savant
I'm curious as well, what function is the +- for?
Could be a image magnification preview switch for use in portrait (verticle framings) mode shooting - plus to get 1:1, and minus to get back to normal view. There's also a protruding finger shelf on the front of the grip, and record button on the bottom grip, both assumably for portrait style shooting use.
Then again, it could be a control rocker switch for use with the RED Electronic Lenses, which may have AF, IS, and other auto features if they stay in the final specifications.
Then again...it could be a user-assignable switch for a number of different functions...program it to control what you want/need.