UPDATE: Okay, that didn't work. I thought that if I changed the settings to "anyone" can comment, then folks wouldn't have to register.
Obviously, I was incorrect (who'da thunk that?!)
So, it looks like you have to register to leave a comment. But, it's a pretty painless process [ed: nice alliteration]: just click on the "Blogger" icon in the upper left corner. It'll walk you thru the process (it's a little weird, because it also asks if you want to set up a blog yourself). You can register with a throw-away email (e.g. mail.com, juno.com, hotmail.com, etc).
I really want to have people leave comments, to get a dialogue going. So....Please don't be intimidated, go ahead and sign up!
In response to some emails, I've changed the settings for comments so that anyone can post one, not just registered folks.
Don't know how long I'll let that go; I'm new to this, so I'll play it by ear.
Meantime, it costs nothing to register (just click on the "Blogger" icon in the upper left-hand corner and it'll walk you thru), and it may help avoid hassles for folks later if/when I change the comments settings back to "registered users only."