In theory, yes - PCM (and TrueHD and DTS-HD Master Audio) will be clearly better than Dolby Digital. Dolby Digital and DTS are lossy compression algorithms (think MP3, WMA, or AAC on steroids), while PCM is completely uncompressed (think CD or WAV file) and TrueHD and DTS-HD MA are compressed losslessly (think FLAC or DVD-Audio). A good way to understand the benefits would be to look at how DVD-Audio compares to DTS with a DVD-Audio disc that offers both (like Blue Man Group's Audio album). DVD-Audio uses MLP (Meridian Lossless Packeting), which is exactly what Dolby TrueHD uses for its lossless compression. The benefits should be pretty immediately audible with movies, although music (like Nine Inch Nails' recent concert release) may actually yield the greatest benefit. It's all a matter of how willing you are to invest financially in the formats. Personally, I'm starting to think about waiting until late this year or early next year before trying to find a sub-$500 Blu-ray player or sub-$800 combo player with a better feature set (at which point I'll probably still leave my Oppo 981HD on the 7.1 Direct input for DVD-A and SACD until HDMI finds its way into my processor in the next few years) - but that's just me and a bit of a stubborn streak regarding the format war. After all, my 7.1 Direct input is presently occupied by an analog connection for two competing audio formats that pretty much killed each other with their recent format war.