This is the best answer I've seen on here so far as to why Quora isn't ready for prime time, and why sites like Reddit will end up delivering better content over time. Sure, all of the atrocities mentioned (downvoting into oblivion, banning, etc) happen on Reddit too. However, when it happens there, I'll remain butthurt only as long as it takes to switch to any of my other accounts. The concept of karma exists there only to validate one's reputation to self, and not to validate one's reputation to others. By creating a more ephemeral concept of identity, Reddit has solved the 'ego' problem.

In the future, I see social networking sites dividing into one of two camps : sites like facebook, which are about vanity, and sites like Reddit, which are about content. It would be best for future entrepreneus to decide up front which camp they're in, long before they face the pickle Quora is currently suffering from.