Now, the authors of the blog comments are foaf:Person. For extra smushing pleasure, we also have a foaf:mbox_sha1sum of the author. So we should now be able to tell, through an InverseFunctionalProperty, who exactly wrote the comment.
I had to add a new property,
blogcomments:hasComment, to link an entry to a comment.
Use Case: "Allow people to comment on my blog who have successfully commented on blogs found in PlanetRDF.org"