The AF, WB, ISO button are on the same/similar spot on 50D, relatively speaking since 50D & 7D dimensions are little different. On 50D the LCD backlight button is to the left of WB, further toward the built-in flash. My point is that if they're going to have button for something, might as well be somewhere that can be used functionally.
I didn't even see that, and obviously wasn't paying much attention at Canon workshop when I briefly handled a 7D. I take it it's customizable?