Okay... the advanced usage script (and keyword tracker backend) has been update to work with the changes MSN has made. So if you want to continue tracking MSN results, you need to update your advanced usage script (from the preferences in the Keyword Tracker).
What's this update for, Shawn? What MSN changes? I hadn't noticed anything different EDIT: never mind, just found this thread http://forums.digitalpoint.com/showthread.php?t=33929
If you want the technical details... http://www.digitalpoint.com/~shawn/2005/10/msn-requiring-cookies-for-rss-readers.html
You can leave it there... The backend isn't currently using the new functionality, but at least I can decide to use it on my end without you needing to update anything again if they switch back.