I've posted a shortish essay on the subject at the National Humanities Center's "On the Human" blog, and there are already some terrific and interesting comments from many philosophers, including Ralph Wedgwood, Peter Kail, Gilbert Harman, Nick Zangwill, Michael Ridge, Paul Bloomfield, Jessica Berry, Joshua Knobe, Maude Clark & David Dudrick, and Paul Katsafanas, among others.  Most take issue with the argument for moral skepticism (no surprise there!), though some raises interesting issues about the interpretation of Nietzsche.   I will reply to the comments (or at least to some main themes in the comments, since they raise so many good and interesting issues, it would take a book to do them all justice) in a week or two.  More comments are welcome ("On the Human" requires that you use your name and the comments are moderated for relevance etc.).