If you're running a proper system, then the events (as they happen) are shipped elsewhere. If you've got a public facing FTP server, then (unless it's getting the throughput of something like sourceforge) you should have all commands sent to a machine that has no other link to the system in question, and have automated processes monitoring this constantly.
I believe (although I only looked in passing, I'm not using IIS) that the bug is triggered by accessing a specific named directory - therefore looking for that name in the logs will find the attempt.
No, this is not a good solution, since it detects it after it has been attempted - however, anyone that has this setup can now look back to make sure that they have not been hacked already.
Other than that, you're faced with just assuming that your machine has been hacked, and if anyo of your systems are vulnerable doing a full reinstall.
Not everyone is in the same situation. For some companies, anonymous FTP is how they receive bug reports (including things like core files that are too big to be HTTP uploaded through most business proxies). Therefore there are a lot of very "clever" admins out there that have still got anon FTP enabled. Obviously, they tend not to be running IIS for this, but it's still something to be aware of.