They had this on the Ticketmaster website for their recent tour in Australia, I emailed them to clarify what this included/excluded (Eg - mobile phones: allowed or not?). The reply I got was that no professional recording equipment would be allowed in, but digital cameras, mobiles were fine. I think they allow this so fans could take photo (as Hanhinator previously stated) and because they can't produce professional quality.
Though, it would be cool if they did bring out another live DVD (I love watching Live in Texas). It would be especially cool if they had either a few different shows from different locations (but this might be asking too much) or at least songs performed at different locations