Ken Rockwell likes taking little digs at us poor Windows users and today he pointed out that Apple's built in image viewer is a good tool for viewing RAW files and can also do some small edits.
Well, that's nice, but Windows users have some free apps that do that, and do it better than Apple I think. Raw Therapee (THe Experimental RAw Photo Editor) is a FREE full featured RAW viewer and editor that runs on both Windows and Linux. I reviewed it a few years ago and it looks like it has only gotten better since then.
As for a system wide image viewer that works with RAW files, there is Google Picasa. It is a free viewer that is great for organizing images and has some decent editing tools as well. But what really shines is that you can set it as your default system image viewer. If you double click an image, Picasa Photo Viewer will instantly launch and display the image. It works with JPEGs, GIFs, PNGs, TIFFs, and RAW files. You can scroll through all the images in the same directory using the arrow keys. It also lets you zoom in, star, rotate, upload, email, and edit in Picasa.
Picasa is my favorite photo organizer, but for series editing I use Adobe Lightroom. It is not free, but it is well worth it for quickly editing a lot of image with very powerful tools. It uses the same RAW processor that Photoshop uses but is much better tuned to working with a lot of images. Lightroom 3 Beta is available free now, but will only function until June 30, 2010, so grab it now and take it for an extended test drive.