When we where looking into Office 365, on the ADFS login screen, we found we would prefer it if the user could login with the network username instead of email address. This is so it matches the rest of our services. with Active Directory Federated Services 3 we found on Server 2012 R2 wouldn't allow us to do this out of the box. The next closest thing was logging in with domain\username format.
However thanks to users on the Microsoft forum i have put some
Updated 18th July 2014 at 12:12 AM by FN-GM