I've seen this elsewhere and I think its a good idea. It seems to help cut down on the clutter when someone posts a large image or replies to a post that contains pictures. The pictures in the quoted message are automatically given [thumb] tags rather than show the same image full size. If someone wants to post a large, hi-res image they can use the thumb tag, allowing users to click on it if they want the full-size view.
Thanks,
Thanks,