The EXIF data will have more info than you probably care about - which WB setting, actual focal length of the lens for that shot, whether or not the flash fired, time it was taken - along with shutter speed/aperture/ISO.

Like Steve says, a notebook is still a good idea to know how you set things up, or what you metered on, why you tried something, etc. Some of it (if not all of it) will be visible right from the camera, but Photoshop or any other editing program will display it too.