Wow!
7 times faster than iphone 4
Voice commands
8mp camera
Siri (Voice commands)
A5 processor
HD 1080i pixels video
iOS 5
icloud for managing all your stuffs like music videos
The sharpest, most vibrant thing you’ll see on iPhone 4S is everything. The Retina display is the highest-resolution phone screen ever. In fact, the pixel density is so high that the human eye is unable to distinguish individual pixels. But without a doubt, you’ll notice crisp text, sharp graphics, and stunning images. It’s more remarkable than the printed page. And you’ll be completely absorbed.
Thousands of apple apps like itunes etc:-
facetime etc
look at this video