I'm guessing it'll be like most new formats - probably pricey at first, and then it will normalize after some time
EDIT: "Warner is not proposing any generic name for the new format, beyond simply "DVD album." The company plans to encourage retailers to stock them alongside normal CD albums on shelves, and they would likely carry a higher price tag, though just how much higher will probably be determined by the amount of extras included on any given disc. The company plans to continue releasing albums on CD, too, for the foreseeable future.
But there are some stumbling blocks that may discourage consumers from embracing DVD albums. The new discs would not play on normal CD players, meaning consumers could not simply pop their new discs into their car stereos or other players. And users would not be able to copy the main audio mix onto their computers. On the proposed DVD album, the main audio mix is to be protected by the same software that already protects the content on normal DVDs."