Turns out that you can already comment my blog posts on FaceBook (also if they become "notes" as soon as they hit FaceBook).

Everything I write here gest on my FaceBook page via RSS. And once it's there it can be commented (not sure this link will work for you).

All we need is a way to get a link and the number of comments back to the blog.

P.S. You can comment this post on FaceBook here