In information readout for Hairspray, PDVD7 said "DTS-HD 5.1", PDVD8 now says "DTS-HD Master Audio 7.1", regardless whether you have PDVD set to 6 or 8 speakers. I've done some A/B comparisons, and although I'm only using X-Fi to Z-5300 speakers (which are great for what they are), there is definitely a difference with Hairspray, there is slightly more depth to the sound now with PDVD8. I'm pretty sure it isn't a placebo effect, I went back and forth a few times in the same scene.
With Fox titles I'm not so sure... I can't seem to make out much difference between 7 and 8 in how it sounds... also PDVD8 does the same thing as PDVD7 just as Fox titles start to play... before the lossless bitrate starts, the bitrate stays fixed at 1560kbps for about 1.5 seconds after the Fox logo just as the movie starts. The possible explanations I see are... either PDVD8 still only outputs core DTS for 5.1 tracks (which is unlikely), or PDVD7 actually did decode MA for 5.1 tracks (probably unlikely too), or that it means nothing and that is normal. What do standalone players which decode MA internally do? In their bitrate readout do they do the same thing?