I know this does not have anything to do with your edit, but...
"A new 2-disc Special Edition DVD of Serenity has been announced for Region 1 release on August 21, 2007. According to Whedon, the River Tam Sessions will be included, along with a new cast commentary, although the latter has yet to be finalised. The reason for this release, says Joss, is the excellent sales figures for the "Normal Edition" DVD.[35]"
FF