First, users may call WIHU from cmdlines.txt for creating user accounts and modifying it's profile data (shell folders and environment variables for example) which wasn't possible till now. Primary user however can not be set here, i.e. creating new account and use this as primary user isn't possible at this stage.
Secondly, folder security attributes are now Windows conform, i.e. there shouldn't be any problems any more with file security settings.
There is another thing that was added, which wasn't mentioned in changelog. WIHU will always create new user profile directory in the form:
%DefaultUserProfiles%\%UserName%.00000001 ... %DefaultUserProfiles%\%UserName%.99999999 if already exists otherwise.
Profile directory creation will not be dependend on Windows any more.
I could explain this in detail, but this isn't significant here to explain because these are internals.