I just noticed something very odd. I was looking at comments posted on my blogger account. I noticed after many of them there was a series of periods. I happened to mouse over and noticed the status bar showing links. There had to be twenty links pointing to adult content. I deleted all the comments. I thought I'd share because it upset me. I wouldn't mind some dialogue in a comment and someone putting a link to their website but this seems unethical to me.
Moderate your comments before publication. Simple as that. If any of them look remotely dodgy, cut 'em down.