I can’t help but feel there’s a huge opportunity for someone to create a true social commenting plugin, that works with public APIs on Twitter, G+, Facebook, YouTube, etc, to integrate actual comments around a blog post, all in one place, in a single thread.
Perhaps set a minimum unique word count, so you don’t pull in RT’s or “I agree”, “great post”, etc. Livefyre comes closest with its SocialSync – still, be great to see unified approach.