Well, most of you know that Enable / Disable 3G options isn't valid with iPhone 4S running on iOS 5. Disable / Enable 3G option was a good option in iPhone 3GS and iPhone 4 as 2G saves battery life than 3G. Apple has fixed this problem starting from iOS 5.1 beta 3. Keep reading after the jump.
So far, this option still available for developers only as it appeared in iOS 5.1 beta 3. iPhone 4S users will be able to use this option after the official release of iOS 5.1. So when Apple releases 5.1 for public ? no one can answer you about this question, as Apple didn't announce any official release date for iOS 5.1 so far. But most floating rumors claiming that Apple will release 5.1 for public along with iPad 3 next March.