If this is true then Apple will for sure be doing one phone that covers both low and high end. No iPhone 4 as a low end model. They will use this one.
By the way, I think that it will be called an iPhone 5 no matter what. I don't think Apple will say "Here is our new A5 chip, new iOS 5, and new 5th generation iPhone called the iPhone 4S."
That's why, when I saw the sticker picture of 4S and its Model # and IMEI/MEID #, I saw it as even more confirmation that there will be a separate iPhone 5. Why would you not call your 5th generation model that houses an A5 chip and runs iOS 5 the IPhone 5?