I'm wondering if I were to dynamically generate a favorites xml file file from a list of hostnames, how would I generate the FavID value?
It looks to be made up of 5 hex encoded parts. Perhaps I can leave it blank and upon import it will automatically be filled in?
<FavID>d5a268b3-ca2b-4160-8e9a-04dbdb3ac8cf</FavID>

The FavID is a randomly generated GUID, so use any randomly generated GUID. :-)

From PowerShell, you can use: [GUID]::NewGuid()