DVD-ROMs will not be able to tell if they have been backed up because they're, erm, totally ROM.
As to BD and
HD-DVD, I don't know. The new copy protections are pretty awkward.
It may be that it also meant that the DVD-R specification (not DVD+R) requires the burner's model name to be written into the lead-in. Most burner models such as Pioneer, LG, BenQ and Plextor also write their serial number into the lead-in, making your backups on DVD-R trackable. LiteOn, who apparently care about your privacy, don't do that.
