This could also work for wikis: Blogs which support autotrackback will then "ping" the wiki page with the url of the blog entry, the blogger's name, and most of the blog text. You could add an invariant section to each wiki page to show the trackbacks. So, you'd have the standard wiki page, then a list of sites that's referenced that wiki page with an excerpt of their comment. That would allow bloggers to put their personal diary on their home page in a single place, and reference the appropriate wiki community. And this in turn would create backlinks from all the wiki communities back to the blog.
OddMuse uses a simpler mechanism: Whenever somebody visits a page on the wiki, the script checks the referrer. If the referrer contains a reference to the wiki site, then we assume that it links to the current page, and we put it in a list of referrers for this page. [1]. This is not the same thing! Phil Ringnalda has a short discussion about autodiscovery and the death of trackback [2] where he compares TrackBack and PingBack?. Pingback just links referrers, while trackback used to require an conscious decision. Phil argues that this increased its value; consequently he feels that adding autodiscovery to trackback reduces it to the level of plain pingbacks -- and essentially, the OddMuse implementation is just that. It only solves the basic problem of converting referrals to BackLinks.
TrackBack has additional benefits: It includes bits of the post in the ping, and it doesn't require an actual link. To quote Phil Ringnalda again, Suppose instead that John has a FAQ post, explaining how to do something, and Jane publishes a post asking the world how to do that something. By sending a ping from his FAQ post, John provides a link to Jane and any readers of her post to his answer, but there's no reason to have a link in his post to her question: people already reading the answer don't need to know the question. In that case, autodiscovery based on links in the entry isn't enough. [3].
As to the interface, this is what Phil says in one of the comments: I'd do it as another form button: my choice for workflow would be type an entry, click "preview", click "autodiscover", select which to ping, click "save". I suspect I'm sweeping back the tide wanting people to manually decide to ping, but that's what I'd like to see. [4]