• by Joe Mandese  @mp_joemandese, July 30, 2010

Based on conversations with its biggest customers - the major broadcast networks - it does not appear that Nielsen will make its self-appointed deadline of Monday to begin implementing a plan to change how it "weights" its national TV ratings, including mathematical adjustments that would reduce the representation of homes with computers connected to the Internet, and would boost the representation of younger households.

During a briefing with Nielsen on Wednesday, the major networks, especially CBS, said they were opposed to implementing the changes until a thorough review of the impact of the changes on TV ratings could be made, and until the industry ratings watchdog, the Media Rating Council, could sign off on the process.

In meetings and communications with various clients to date, Nielsen executives have implied that the MRC had been fully briefed, and had already endorsed the move, but it became evident during Wednesday's briefing that is not the case, and some clients said they believe Nielsen is forcing the issue and trying to ramrod a process for business reasons other than managing the quality of its national TV ratings - principally, the introduction of its so-called "Extended Screen" service, which will measure viewing of TV programming done via computers connected to the Internet.

Nielsen executives have told clients they need the new weighting controls in place at the start of the 2010-11 TV season in September, in order prepare for its Extended Screen service, which is expected to be released no later than February 2011.

CBS executives expressed the greatest concern over Nielsen's rush, and the fact that the MRC had not yet vetted the plan.

The broadcast network reaction was different from those of some cable networks, especially Turner Broadcasting System and ESPN, who have been pushing to accelerate the changes, and some clients believe the divisions have to do with potential competitive advantages or disadvantages they weighting changes could have on ratings for various networks, which could manifest in gains or losses in advertising revenues.

Nielsen executives have maintained that the sample weighting adjustments would have only a miniscule impact on actual ratings, and primarily around periods when Nielsen's sample households install new consumer electronics, usually around the Christmas holidays.

While changes in computer/Internet access is one concern, some Nielsen clients believe CBS' reaction is likely based on Nielsen's plan to begin giving more weight to households headed by people under the age of 25, a demographic the network skews low on.

Meanwhile, a Nielsen spokesperson took issue with MediaDailyNews' report earlier in the week that Nielsen disclosed to clients that it did not have the ability to measure TV viewing done via Apple computers connected to the Internet. The spokesperson said the revelation was not new, and had been previously disclosed to clients, and that Nielsen has a solution that will enable it to begin tracking TV viewing via Apple computers beginning this fall.