I am never quite sure how much the Nielsen ratings actually work, in fact I am never sure how much they actually say about who watches what, but I will digress. I was reading an article over at Media Buyer Planner who discussed the new Nielsen rating which allows shows to count both the original airing and subsequent airings of the show to be counted all at once. Here is what Media Buyer Planner said about how this could effect the ratings of Heroes:

For its premiere episode of Heroes, NBC is taking advantage of a new Nielsen rule that lets networks combine the ratings of multiple runs of a show - the original airing and any subsequent airings - and report them as one number.

Monday’s episode of Heroes will be repeated Saturday night, and the numbers for both broadcasts will be counted together when Nielsen releases its final numbers for the week, writes Variety. Better yet for NBC, the Saturday repeat will not be counted in NBC’s weekly averages, which means that the network will be able to eliminate what may well be one of its least-watched hours while at the same time boosting the audience average for the show.