You might be thinking, "I haven't used Web Folders since Windows 98" but if you have used Sharepoint or anything with WebDAV, you are using Web Folders!
You can download and read about the May 2007 update
here.
Fixes in this update
#1: A document that is opened from a Microsoft Office SharePoint Server 2007 site may be downloaded two times when you click Edit in Microsoft Office program.
#2: The download progress indicator does not work for some documents on the SharePoint site.
#3: You cannot rename or copy files that have a display name in a non-Internet Information Services (IIS) Web folder.
#4: Security Enhancements.
This update replaces the January 2005 Web Folders update.