I know we've all been discussing the video format for Sky's HiDef service, but what about the sound formats. Sky state that "many of our HD programmes will include a Dolby 5.1 surround sound track", but that raises a number of questions in my mind: 1. Does this mean Dolby Digital (AC3), or Dolby Surround? My guess is AC3. 2. What sound format(s) gets output on the HDMI interface? 3. How do I find out the capabilities of any particular HDMI implementation? For example, I've got a Samsung SP46L6HX TV, which has an HDMI socket. But, how would I find out whether this can handle an AC3 soundtrack? Any thoughts on this?