'Of course, now that I think about it, if everyone did that, it would seriously destroy the rankings, permanently enshrining those 40 links in the list since they would be linked from every site via the RSS feed creating, in essence, an infinte loop. Interesting!'
Quick point: I hit this exact problem (conceptually) with a project I'm working on. The answer is to tag the links in the RSS feed, and have DayPop ignore a link if it has that tag.
Unfortunately, coming up with an XHTML tag is fairly difficult, since we'd like to place it in the
<A tag itself. Probably the best thing is an obscure
class value. (You can't just randomly create an attribute, because it's not compliant. Bleah.)