I have gotten a few SPAM comments so far, so I have decided to turn on the Word Verification. Basically what this means is when you post a comment, you will see an image which has some wavy-looking text. Type that in before submitting your comment. Sorry for turning this on, but it is important to me that people can post comments without needing a Blogger account, and I cannot think of a better way to get rid of the SPAM comments.
If you have trouble posting comments, check out Blogger's help page for the Word Verification feature.