4th iPhone = iPhone 4.
5th iPhone = "iPhone 5" (yet to be determined).
People saying the next iPhone will be the iPhone 4S are also assuming the iPhone after the iPhone 4S will be the "real" iPhone 5. Wrong. That's the iPhone 6. There's no way Apple would ever name the 6th iPhone "iPhone 5"
.
5th iPhone = "iPhone 5" (yet to be determined).
People saying the next iPhone will be the iPhone 4S are also assuming the iPhone after the iPhone 4S will be the "real" iPhone 5. Wrong. That's the iPhone 6. There's no way Apple would ever name the 6th iPhone "iPhone 5"