Trackback is one of the more nifty features of the Movable Type weblog system. It allows blogging web sites to “tell” other sites that they have been linked. The system works via a single “ping” XML-RPC call that passes over the URL of the linking web page, a short description or excerpt and the title of the news item.
Long suffering from the not-invented-here-syndrome, UserLand, maker of the blogging software Radio has implemented Trackback as well opening up dynamic link reporting to many thousand sites more. This is a good thing (TM). Congratulations.