If you've Vista and tried using the "improved" backup, you likely hate it. I hate it so much I switched to using Robocopy to get a selective differential "backup" (with ACLs), but anything in-use ...
Ever deleted a file or folder on a file server and didn't mean to? Yea, me neither. But if you did, what would you do about it? Maybe you'd break out the backup tape or perhaps perform the restore ...