When it comes to patent applications Apple are always applying for them, and the latest one could be implemented on the new iPhone 4G. The new feature that Apple could be working on would see the iPhone user control incoming calls just with a swipe over the camera lens. View a video of the latest renderings of the new iPhone 4G
If this new feature makes it to the next-generation iPhone, then you could even rewind and fast-forward your voicemail messages as well. According to an article on DeviceMAG, you could even be able to control your iTunes library, turn a page or scroll a webpage with this new gesture feature.
The user will not need to touch the lens, the system is all gesture based. There is also the possibility that with a simple tap of the phone other features of the new iPhone 4G could be accessed. The patent was filed back in Q3 2008, so makes you wonder if we will ever see this feature, only time will tell.