I wonder about this, too. My guess is that they are afraid people would make fake accounts and game the system, though people are gaming the system with link f

I wonder about this, too. My guess is that they are afraid people would make fake accounts and game the system, though people are gaming the system with link farms anyway, so... I think another comment that I saw on a different article had the right idea where they should use the votes that people in your social network make, that way some Spammer making a fake account and upvoting stuff won't affect you unless you are friends with him.