We discuss this on this post #6315

Ideally we can come up with a solution where we use Bitcoin to our advantage rather than recreating the problems of other communities by using all the same solutions.

I'm going to be thinking about this a lot through the end of the year. Seems necessary to find solutions if we're going to scale. Worst case we can mod, downvote, and weight the ranking algorithm a variety of ways. Best case we use Bitcoin to create something where spam, attacks, etc. make you lose significant money, ie What Would Satoshi Do?