I'm getting enough spam (disguised advertising) comments that I have to do something.
I sure don't want to discourage comments, or even slow them up by using the "moderate comments" feature that requires me to approve them all.
On the other hand, I don't want the comments larded up with this anonymous spam.
So what I thought would be the least trouble for those posting comments, and for me, would be to use the "word verification" feature. That will add another 5 seconds to the time it takes to post a comment, but at least you'll know that when folks see that a comment has been posted they will know it's for real and will be more inclined to read what you've written.