I use Contribs 6.5b2 ...
Ufficial, stable 6.0.1 is obsolete and unsecure, My system has been compromised !

Add interface for create/delete/manage MySQL DataBase...
Add interface for set bandwith limit in anonimous FTP.. es: max user, max connection per host and max bautrate.
Add interface for activate/deactivate unused service, and restart active service.
Add this option for samba: deactivate unix extension
Add nfs support for user home and ibay for more support to Linux/Unix client.
Add secondary, minimal, webgui for enable single user to change its password independently to server administrator
Add interface for edit firewall rule, es: open or close port to internal or external interface, this is useful for running extra service over the server.
Add functional Hylafax server built in.
Add software auto-update via web or via CD with not need restart server.
Add, in backup option, function for backup over external USB Hdd or remote backupserver ...
Backup to desktop it always fails for browser filesize limitation...
The DAT Unit they are expensive, slow and unsecure ... add data verify to backup script !