Apple went through a lot of work to make the prototype look like a regular 3GS. They made a custom case for it to look just like all the old iPhones. I think it is quite possible they also put a screen on the prototype that is similar in size to the old screen. The only reason it is a tad smaller is that they made a smaller mock up of the larger screen final version to test the resolution. So my question to you, do you think my theory is possible and if it is true, will you be upset with a larger screen size? Assuming they make the bezels smaller to not increase the actual size of the phone very much if the screen is larger.