In response to something Sarah brought up about photographers who want to shoot good photos "on the fly" and don't want to spend time post-processing; seriously check out Google's Picasa. It's a great image viewer that supports nearly all image formats, including RAW. It works great with my Pentax RAW files, so I assume it works as well with Canon, Nikon and Olympus cameras. It's fast and easy, and allows you to do quick adjustments without saving over the original images, and is especially handy with RAW because it has a very nice white balance tool (not as good as Adobe's, but still useful) that can correct an image almost instantly.
I'm very big into Adobe Photoshop and I like using Bridge, but Picasa is always my first stop after a photo shoot because it's just so fast and easy and a quick way to sort out the keepers.