I think for the iPhone 5S to be successful it will need to take market share from non iOs. Just having existing iPhone users replace their phones will just put Apple on par with a utility stock. So what would it take for Android smart phone users who are already users of iPads or Macbook Air to switch to iPhones?
1. The text input in iOs is very slow. The swype utility in Android is essential to many, because of the rapid speed at which one can enter text and that too with just one hand.'
2. Ability to customize the home screen by shortcuts like direct dialing.
3. Ability to block calls without having to jail break your iPhone and buy an App.
4. Increase the width of the current iPhone without increasing the length (height).
What will #4 do?
The iPhone 5 went to a standard size ratio.