Photo Stream isn't limited to shots taken on your device's camera. It also works for images imported to your iOS device (say, if you're backing up your SD card to an iPad by using the Camera Connection Kit). New photos are stored only for 30 days, but if you want an image to stay on your device longer, you can save it to your Camera Roll. Your Mac or PC will keep all photos that come through the stream, not just the last thousand.

The most important upgrades to photography in iOS 5 are the addition of the photo button on the lock screen and the support for the volume-up button as a shutter. Those two features go a long way toward making the iPhone work more like a dedicated camera.

The upgrades to the Camera and Photos apps are great, because they set the bar high for all iPhone photography apps. That said, habitual and users may not even notice they're there.