It would be all very nice of me to attack bloggers who give up on comment spam and no propose solutions. My main piece of advice for bloggers is to use up to date blogging software and to use the built in spamming solutions that many of them have built in or available with plugins.
While spam killing plugins don’t stop everything they do help.
What does slip through the filters and plugins needs to be diligently monitored and checked manually either before or after they go live on your blog. There is no other way to ensure blogs are spam free than to have someone monitor it. If you’re not willing or able to do this then you might also like to consider the option of either switching off comments on your blog or disabling them after a certain period of time.
Maybe I’ll give that a try. In the meantime, I’ll keep the moderation on.
UPDATE: Did you know that even Scobelizer started moderating comments? He’s not doing it because of spamming, but he’s still doing it.