about all of the lip synching issues is *trying* to show off your setup to someone who knows NOTHING about HD or technology in particular......and the ONE thing that stands out and smacks them in the face (other than the sharper, more vibrant picture)....is the fact that the audio/sounds don't match the video/picture!!!
Both of my 50" HDTV's have an HDTIVO hooked up...and these are *usually* the TV's that we're watching when entertaining....and it's been VERY evident the last few weeks that the audio is off from the video...most noticeably on the D* channels (as opposed to my OTA stations).