I was being general on the Feed side, as ATOM/RSS are so abused anyway that just because a specification says it includes something does not mean anyone conforms to it. But for us the URL was never a good means to identify the commentor purely because it can be abused, so we are very black and white on this, either its anonymous or its properly authenticated.

For the mass market (the only thing we care about) url’s are a no go anyway (as stated in the post) – but as more platforms are making their identity available through API’s (e.g. Facebook + Myspace) I see a good future for comenting.

We absolutely agree that authenticated commenting is a good thing. A few things of note, BackType does very little scraping. ATOM feeds _do_ contain urls and we do make use of APIs that allow to ensure authenticated comments.

This is still something we are working on and is one of the reasons why we like systems like Disqus and IntenseDebate.