it's source,
film, upconverted to HD, it's actually not a bad job concidering that it was never intended by the director to be seen in HD, if you noticed, the outdoor scenes (daytime) were very very good. I think this is attributed to using a different exposure time or something for the indoor scenes, creating a "grainy" appearance. I also read from last week's post that the same guys that do the other hd-transfers (abc, cbs, etc...) did this same one too.
i say cut them some slack, this is among the first batch of shows from nbc to get high-def treatment, it will improve. I've seen worse HD programming IE: all those shows that are on torch mode, thinking that the extreme contrast is some cooler - more detailed image.