This is something all you IIS admins are going to get a kick out of me not knowing already.
The IIS Admin tool has a nifty-looking feature that lets you back up the configuration of a web site, and a tool that will allow you to load that configuration on another server. I thought this looked like an awesome idea.
Here's the list of stuff it DOESN'T think is part of the web site when you back up the configuration:
Any contained virtual directories
Any contained virtual sites
Any contained applications
So basically if you have a website and use this tool to back up the configuration, it doesn't even get the job done half right. However, to compound the stupid, you can actually go through and back up and import every single one of those things by itself and it will import correctly. So they've got the code written to back up the configurations, it just DOESN'T WORK.