The networks have been hinting at moving the debate from time-shifted program ratings to commercial ratings for months now, but the strong buyer's market during this year's upfront side-tabled that discussion, and 2006-07 upfront ad deals have been guaranteed on the basis of "live" only ratings, a move that recent Nielsen data suggests could cost the networks as much as a fifth of their TV audience value over time.

In a meeting believed to have taken place last week, the broadcast networks finalized a their commercial ratings plan with Nielsen, which will be based on all audience exposure - both "live" and time-shifted viewing. The new ratings will represent the average of all commercial minutes running throughout nationally distributed TV programming. They will not represent ratings for individual TV commercials.

Nielsen plans to begin providing the data this fall and will give the industry most of the new broadcast year to evaluate it before making it the new currency of the 2007-08 TV season.

During that period, Madison Avenue is expected to weigh in with its own TV commercial ratings plans, including a push to report the data separately for live and time-shifted viewing the way it is done now for program ratings: in installments of "live," same-day playback and seven-days of playback.

"We anticipate that other national clients will want to look at these commercial ratings differently," acknowledged a Nielsen insider, adding that the company plans to provide that, as well.

"I suspect this will be controversial with respect to which of the commercial [ratings] various parties use in negotiations. But that's up to them to work out. Our job is to provide the data," said the executive.

Those conversations are likely to be as heated as the ones surrounding time-shifted ratings guarantees that led up to 2006-07 upfront ad negotiations. According to a copy of a little known Nielsen report obtained by MediaDailyNews, the impact of time-shifted viewing will be profound on the broadcast networks.

The report, which analyses the characteristics and tuning of DVR homes in Nielsen's sample in March 2006, finds that 10 percent of total viewing in those homes was done in playback, and more than 18 percent of prime-time viewing was done in playback. While the percentage of DVR homes in both Nielsen's sample and the U.S. TV universe is still deemed low, it is growing fast and could begin to have a profound impact over the next few years, creating a significant incentive for the networks to find a way to reincorporate playback the official currency of the TV advertising marketplace.

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