Bridgy lets you post to social networks – and comment, like, reshare, and
more – from your own web site. It also pulls other people’s comments, likes, and
reshares of your posts back to your site. In
IndieWeb lingo, Bridgy lets you
POSSE to
the silos easily and
backfeed the responses
automatically.
Check
out this example
, or see the docs for more details.

from: Bridgy

This looks like a really exciting development in social media. Recently most of the commentary on blog posts has moved to twitter, g+ or facebook. This looks like it could link that up and push out posts and then pull comments made on other sites back to your blog.