I know, I should just bite the bullet and use Aperture. But short of that, when I connect my Canon G10 to my computer, iPhoto helpfully offers to import all my photos...which include the RAW files I really want and the JPEG previews that are created by the camera automatically, so I get two of each photo. There is no way to shoot RAW only on the camera that I am aware of, but that would be a solution of sorts. I think the camera display only shows the JPEGs on the screen for the preview function...that would be something to test.
Automator would be a possible option, I guess. I will have to look at what iPhoto commands it offers. If anyone's done this with Automator, I'd love to hear your solution.
But even Automator is a solution after the fact...what I really want to do is not import the JPEGs, not import them and turn around and delete them. It offends my sense of hackerly elegance, I guess. But I'll settle for not having to do it by hand. :)