You're right, the drive reports the DVD+RW media as blank until it's
been formatted. Since then there is no way to "unformat" it, you can
just write zeroes to a couple of sectors at the beginning of the disc
and this may vary depending on the software you use. Generally the same
applies to DVD-RAM,
I tried this here, and it a freshly unwrapped blank DVD+RW I get the
correct result with both the lucid and the upstream git head version:
ID_CDROM_MEDIA=1
ID_CDROM_MEDIA_DVD_PLUS_RW=1
ID_CDROM_MEDIA_STATE=blank
ID_CDROM_MEDIA_SESSION_NEXT=1
ID_CDROM_MEDIA_SESSION_COUNT=1
ID_CDROM_MEDIA_TRACK_COUN
