I have my comments moderation turned on. So before a spam comment can hit my site, I am asked to approve or reject it. Today I got a comment with a trackback. Of course, it was automated spam. I know that because, I have disabled wordpress comments and only have FB comments enabled.
Now that I have validated that it was spam, I am confident that I can blindly mark as spam and delete every comment approval request that I get. At this time I only get a comment once or twice a month at most. But if this system proves right, I can automatically have them skip my inbox with a rule/filter. Yes!
When a comment does come through facebook however, I can be pretty confident that it was a human who actually read it and commented. Facebook rules. Thank goodness for facebook!