Maybe I'm wrong in this assumption, but I was fairly certain that in Dark Knight, the Dolby TrueHD is output at 5.1, not 7.1. In which case, so long as his PS3 is decoding it and outputting it to his system, he should be able to get Dolby TrueHD without compromise. Regardless, as many have suggested before, in the PS3 you have to manually select the audio format in most Blu-ray movies in order to get the high def formats. Most of the time, the movies are set simply to DD, or DTS/etc.