"One simple way to think about why the newly announced Nielsen/Twitter ratings won't matter much to advertisers is this: Twitter can skew --some might say "be gamed"-- in ways the Nielsen TV ratings (as opposed to the newly announced Nielsen TV Twitter ratings) can't be. A relatively small audience (compared to say, NCIS or The Voice) can make an outsized amount of noise on Twitter as it is. I look forward (I'm not kidding) to the torrent of "RT to Save Our Show
!!! IT WILL BE COUNTED" that will be unleashed on us all.
But as far as the TV advertisers are concerned the loud cries on Twitter will only matter if they make a difference in terms of the number of people who actually watch their commercials and if that happens it will show up in the regular Nielsen TV ratings anyway."