Needless to say, it's poorly documented. Even worse, the documentation seems to center on how to squeeze a one-line summary out of an existing HTML page. Since it's just a little one-line text file, doing a couple of lines of PHP during the highscore-update process was a trivial thing.
Best example I've been able to find is on woot.com, and that seems to be the page that everyone trumpets as being microsummary-capable. Their big example involves putting woot.com on your bookmarks-bar and watching the latest woot-able item appear and dynamically update.
But it's not working for me. I just see the default text on the bar. So it might be something that's not quite ready for prime-time. I'll just see if it suddenly starts working.
In the best of all worlds, you should be able to put a bookmark to confusebox on your bookmark-bar, and you'll see a little piece of text with yesterday's top score-getter that updates every day.
So now all high score-getters can get immortalized on browser bars. It'll be cute if it works.