Wouldn't it be handy if you could post an XML file that's similiar to an RSS file but indexed all the product reviews you had on your website. This file could then be picked up by search engines which could then aggregate them. This would make it so much easier to find reviews and would be a great way to drive hits to websites. Just need to agree on the XML file format and figure out what to do about a product taxonomy if anything. I guess it wouldn't have to be just products; you could review anything.