when will blu ray movies have 7.1 soundtracks as standard?

i know few are 7.1 but when will they become more common?

i currently have a 7.1 system and i want to utilize 7.1 Dolby HD or 7.1 PCM but without a 7.1 soundtrack would have to use the 5.1 Dolby HD track and not use the rear 2 speakers.