Np. The way I think about it, an "icon" for a piece of information has to be three things:

    An accurate portrayal of the contents

    More compact than the original

    Sufficiently different from other icons of the same "type"

With web pages that means more than the title + favicon. If a page has a video embedded in it, that's a BIG clue. Also there is tons of structured information that sites put inside pages to make them more tasty to search engines, like microformats. Facebook recently created a de-facto standard for video_src nd image_src link tags.