According to 9to5 Mac, the iPhone 4S popped up in all its glory in the 9th beta of iTunes. It also looks like the Verizon iPhone. That means two things: either Apple hasn't changed the iTunes placeholder image, or the 4S really is an updated 4.
It might also be an indication of an iPhone world phone designed for all three carriers. We'll know on Tuesday. [9to5 Mac]