M. (or is it X?) at Whuffie comments:

Kevin Marks and Rainer Brokerhoff blogs are ‘abuzz with talk of adding a value system to your html links. That way when you create a link you can assign a value to it to show how much you “approve” or “disapprove” of what you are linking to. While this seems to create a quick and easy Whuffie like system, it is not at all comprehensive, and I have to question if it would really be worth the trouble. Why not just put a header above the link: “I hate this blog, I don’t trust them, they suck, but check them out to mock their very existance” Same effect, no?

I don’t think this is the same effect at all. The proposed link value system is to have a simple way to tell spiders (and similar robots) that scan the HTML for links whether you approve or disapprove of that link. Of course, as Kevin points out, one often will complement this by user-visible styling (or even a header).

While it of course is a “Whuffie”-like system, the effects are not exactly the same – since valued links will usually point at individual posts or news items, the resulting values will not necessarily apply to the whole site. They may not even apply to the item’s author. I agree that it isn’t comprehensive – by design. Rating systems that are installed on a particular site solve other problems entirely, but I’d like a way to say to search engines “here’s a link to this item, but I disagree with it; don’t tally my link on the same list with people who agreed with it”.