One of the questions I get all the time is "how do I open up a JPG file in Camera RAW?" Unfortunately it's not as straight forward as I'd like it to be. Simply double clicking the JPG will open it up in Photoshop as a JPG. However, if you want to take advantage of Adobe Camera RAW's ease of use and non-destructive workflow, I'll show you how you can in this episode of the Adobe Creative Suite Video Podcast:
httpv://www.youtube.com/watch?v=JYvbh-Wxz_k