Depending on how granular your MT categories are and how often you may find yourself talking about TrackBack, you may want to associate this url:

http://www.movabletype.org/mt/mt-tb.cgi?tb_id=3

with a category related to discussion about TrackBack.

To do this, go to "Categories" and create a new category called "TrackBack" (or whatever makes sense to you). Then click on "edit category attributes." On this page, under outgoing pings, insert that URL into the appropriate field and save. Then, when creating a new entry that is about TrackBack, select the category that you've set up. That's it. From then on, you only have to set the category and save for the ping to be sent.

We're planning on adding a resources and tutorial section to movabletype.org; we'll also provide category ping urls for those who write often about MT hacks and tricks.