Many users asked Apple to re-include the button to disable 3G connectivity in the iPhone 4S and this happened in the new iOS 5.1. Even from the beta version of iOS 5.1 we knew that this would come, but unfortunately it does not work exactly as you knew from the old iDevices. If the terminal is reset, the connection automatically switches to 3G and if you are in an area without an EDGE/3G signal, it will automatically return to a 3G signal when you reach an area with coverage, because that's how Apple thought the whole system.
