I think DS9's, a Voyager for that matter, release in HD is inevitable. Star Trek is too lucrative of franchise for Paramount not to upgrade DS9 and Voyager into HD. TV is nearly all HD and if Paramount what to continue to make syndication money it has to upgrade the shows. Whether or not the show gets the TNG treatment of special features we shall see. I would love to see a DS9 cast reunion!!!!
I would love, love, love to see DS9 get the same treatment as TNG. The fact that Enterprise was put onto bluray says something. Yes, ENT was shot in HD, but it was also the least popular of the Trek shows in terms of ratings and Paramount is pouring money into the special features.