Phillip Winn's response to Daring Fireball's TrackBack complaints pretty much sums up my thoughts. Combine this post with Grimmelmann's cultural take on TrackBack and you've got reason to get excited about TrackBack.
Memo to self: The Movable Type bookmarklet took it upon itself to ask me to ping the TrackBack URL for Grimmelmann's post. No muss, no fuss. I post and the work get's done for me.
Now I need to dig in and see how it actually discovered the TrackBack id.