Thanks for the tip x1984x
Spam seems to be a hot issue and I've heard tons of complaints about the trackback feature letting it in. I'm sure that there are plenty of first time blog users who who haven't thought much about the trackback feature, so it you're worried about spam here is my two cents regarding whether or not trackback is necessary:
Unless you plan on writing lots of articles about other people's articles and then sending them trackbacks in the hope of netting traffic it just seems kind of useless. And frankly I don't really care too much if somebody wants to say something about me on their blog so I don't need to receive them.
I don't like the trackback function anyway since (in my own personal opinion, so don't get mad) there's a bit of a desperate quality about telling someone "Hey look at me. I wrote about you, or the same thing as you, on my blog. I really want you to come and look at it." If it was important I'd notice the traffic coming in on my referral logs. And if my visitors care so much about the topic they can google it and get good quality results about it. Who knows what jerk is going to write some trash and then trackback to you.
And sometimes when I check other people's trackbacks it's annoying because another person just used something you said and commented on it in a useless and unoriginal way to get attention. So it seems to encourage spambots and also spamhumans. The more popular you are personally, the more I imagine that this would be a problem. Why can't the person just leave a normal comment saying what they want to say like everyone else (even including a link if they must). Sending a trackback seems to be a selfish attention getting thing to do if you ask me.
Maybe I'm wrong, but I suggest deleting trackback if it's becoming a problem - unless someone can convince me otherwise.
I have a draft email where I stick stuff I've deleted from my blog in case I ever change my mind and want to go get those things and put them back. You could make a file like that anywhere and put notes to yourself about where you got the things from.
P.S. Anyone who uses trackback please don't hate me. Just tell me why you like it and maybe I'll change my mind.