Chirrup is comment system which uses Twitter as a datastore.
People are following your twitter feed. People are reading your blog. People are discussing things they’ve read on Twitter. It seems only natural to marry them up.
It’s pretty common for people to post links to pages via Twitter, along with a short commentary or opinion. The format is so free, with the only restraint being one of brevity, that many people use Twitter not only to post the daily minutia of their lives but to discuss and communicate ideas. Chirrup is just one the of many, many applications which use Twitter as a platform.
Chirrup simply provides a means to show that chatter on your blog as a set of direct responses to the content you’ve written. It also provides a means for people to post their opinions to your blog using a technology they already have and use