Think about it.
If they increase the size of the screen (in width as the iPhone 5 already had a height increase) then there's two options:
1) They will increase the number of pixels displayed to something like 1136 x 700. This would make almost ALL apps incompatible. Way to piss off the devs that are already having to update for iOS 7.
2) They DECREASE the density of the screen to keep the same number of pixels over the larger area. This would result in a less than Retina quality screen. Not happening.
Calling BS on this too.
Or they give the retina a boost in DPI (2.5 or 3X). If you use an HTC one you can see that an increase in DPI can still make a visual difference.