Read today on the Media Drop about problems with people sending trackback pings that have absolutely no relation to the post. It never occured to me that trackbacks could be abused, but it is very obvious once you think about it. All possibilities can be abused and exploited, just like email and comments.
…and it’s not even that new. Googling “trackback spam” gives you more than 9,000 hits! How long will we be able to have trackbacks that doesn’t require approval first?