Superstar
Let me first say that Enrico Penello's iPhone 4S is an unofficial concept. Penello has redesigned the iPhone 4 to address some of the main concerns from fans such as a Wi-Fi antenna and a bigger camera.

Penello's iPhone 4S seems to be slightly wider than the existing iPhone 4 and is designed to run iOS 5 with an A5 processor. The iPhone 4S also comes with a texturized back case to improve grip and a removable battery. On the lower end of the iPhone 4S is a small WiFi antenna designed to help improve the speed of your Internet connection in a pinch. Penello hasn't forgotten the growing population of iPhone shutterbugs in his redesign, adding an 8 MP camera to the iPhone 4S.

The iPhone 4S is of course just a concept, but it may not be too far from what Apple is planning to announce in October. You can see conceptual images of Enrico Penello's vision for the future of the iPhone here.