After a comment by Carrie on twitter and the resulting feedback I'm going to change the comment policy on the blog.
Word verification is now off. This is an attempt to improve the reader experience, because it seems captcha is annoying people a lot.
I have not turned moderation on. This is an experiment to see if I get hit with spam. If I do, moderation will have to go on because I really don't want the spam.
Please let me know what you think works best!