Apologizes to all who received Trackback spam in their mailbox. As I mentioned before, my solution was to remove notification of trackbacks and to moderate them to hell. This didn’t stop the trackbacks, but it definitely stopped anyone but me from noticing it was occuring (We are averaging about 600 trackback spam a week). Anyway, when I upgrade to 1.5 I forgot to reimplement my hack. So I just tried to implement my hack in 1.5 and found wp-trackback.php has changed in Wordpress 1.5. Being lazy like I am, I decided to install Spam Karma (an active comment moderator). There is no option to enable it only on trackbacks so it might accidently moderate a comment into oblivion (sort of). I applied a patch outlined by Mark over on Tempus Fugit that marks spam as spam (instead of deletion), allowing for restoration using Brain Dupuis’ Paged Comment Editing Plugin. I also hacked comment-functions.php to turn off e-mail notification of trackbacks and pingbacks. If all this fails to prevent the spam, I have a final solution: MtDewVirus’ Trackback & Pingback Moderation for Wordpress 1.5 (essentially what we were using before).
Assuming the twits creating the spam don’t change their format any time soon, all spam message look like this:
<strong>sometitlehere<strong>
commenttexthere
This, luckily, makes it very easy to filter. I’d appreciate if no one posting a comment to the blog duplicate this pattern 
#1 by Plurk on March 7th, 2005 - 10:45 am
Crap. Normal trackbacks look like that. *sigh*
#2 by Plurk on March 7th, 2005 - 2:43 pm
I love spam karma
It’s already dealt with 37 spam messages.
#3 by Plurk on March 11th, 2005 - 1:46 pm
Now that is nice. The blog was spamed again (84 messages so far). SpamKarma killed 78 outright, moderated 5, and let one of them through. In its defence, besides being spam, it only included the words nude and photos, which could have honestly been valid words used in a comment. Eliza Dushku, Keira Knightley, and others could also be mentioned in a comment without being considered spam. As it stands, I really should turn off accepting a comment when comments require one to be logged in.