Apple plans to add more functionality to the stock Camera app in iOS 5. One of the features will allow the volume buttons on the side of the iPhone to snap a picture, making it unnecessary to touch the screen. This is much easier and lets the iOS device act more like a standard point-and-shoot camera.
Luckily for those who have jailbroken their iPhones this functionality can be installed right away. A tweak called CameraButtons provides this feature and much more for only 99 cents. To find the app open Cydia and navigate to Sections -> Tweaks -> CameraButtons or find the package using Search.