(Editor's Note: Developer-speak ahead. Consider yourself warned.)
Whether or not iPad 2 will have a double-resolution Retina display is still in question. While most rumor sites have recently rebuffed on this feature, saying it will be saved for iPad 3, this is a reminder of an important lesson: prepare for the inevitable! When creating graphics, a good rule of thumb is start big, export small. It's a whole lot easier to export a graphic bigger than to recreate it from scratch. 340 dots-per-inch, and 2x-4x the size of the final pixel area is usually a good place to start.
As we've all heard by now, iPad 2 will probably have a front-facing camera. Accessing the camera will probably be just like accessing the front-facing camera on iPhone/iPod Touch, with UIImagePickerController. A major difference now is with the added screen real estate, there is much more room to add interesting camera controls or info to the view. Check out the cameraOverlayView property for more information on how to do this.