** Microsoft release patch a week early **
Thanks for the alert, Tom. As a result of the warning I've been watching for the patch, and caught its release today. I went to Windows Update and downloaded the tiny (200K) patch, it installed in seconds, and after reboot my computer came back just fine.
I'll wait for a quiet time to install it on the server. The vulnerability is n/a while the server's operating unattended, and the vulnerability needle rises off the peg only when I log in remotely and fire up a browser on the server and do things like install this patch. I'll wait and do it carefully at a time of my convenience.