Jason Kottke covered this at a higher level, where consumers are taking into account the format of the media and not just the content in their reviews (unlike your average critic working for big media).<p><a href="http://kottke.org/10/03/the-new-rules-for-reviewing-media" rel="nofollow">http://kottke.org/10/03/the-new-rules-for-reviewing-media</a><p>They're leveraging what power they have from available tools (star ratings and reviews on popular commerce sites) to put pressure on the publishers.<p>Is it odd that Amazon doesn't denote (or possibly separate out) reviews from users that it <i>knows</i> purchased the book (or DVD, etc.)? Privacy concerns? The user is already expressing an opinion on something the have [ideally] consumed, thus tying it to their profile.