According to IMDB news, the Blu-ray version of The Descent is confirmed to not work on Pioneer Elite and Sony BDP-S1 Blu-ray players but functions perfectly on the PS3. The reason? The disc utilizes BD-Java technology for picture-in-picture video commentary, which is not supported by the standalone Blu-ray players.
Sony has confirmed that they are working on an update to the player's operating systems, but how are they going to deliver said updates to consumers who already have the faulty player?
[Update 1: It's Pioneer's Elite, not Panasonic. Thanks to everyone who pointed it out.]