No one can say that the move to HDTV is insufficiently supplied with confusion... Some broadcasts are intentionally broadcast as Dolby 2.0 (no reason to do a surround mix of a guy sitting on a soundstage reading the news) while others are Dolby 5.1 - and ads can easily differ from the main program. Thankfully, the local affiliates around here seem to have cleaned up their acts a bit when it comes to broadcasting in HD, as I haven't run into the left/right-only Dolby 5.1 broadcasts in a while. Don't ask how confused I was the first time it happened...