We need:
- tag other peoples posts.
- create governing bodies, like a logics body, which can say if something is logical or not
- be able to subscribe to a set of tags
- tags must be traceable to a community dictionary
- you must be able to challenge a downvote
- voting must take a complex form, like tags
I really like the taging of other people as well as governing bodies, some sort of mods that at least challenge upvoted and posts from users that appear to have a spammy behaviour as well as monitor downvotes. I don't know how much the latter would be needed if this existed. Tags could be possible on a third party website using the api, but than you would need a small community of devoted people from the start otherwise there won't be anything to gain in the eyes of people that aren't part of it.