Nielsen has recently seen a number of challenges to its ratings dominance, mostly in the area of digital. For example, comScore (NSDQ: SCOR) recently created a hybrid measurement product with Omniture (NSDQ: OMTR) that adds traffic and panel-based data in one metric. Also, TiVo (NSDQ: TIVO) and Quantcast teamed up on a system that tallies TV and web usage.

SEE ALSO: As Challenges Grow, Nielsen Looks To Explain Its Digital Media Abilities

Despite flurry of activity on the measurement front, media executives and ad agencies have not been completely satisfied. In September, researchers from major media companies like NBC Universal (NYSE: GE), got together to form the Coalition for Innovative Media Measurement (CIMM) to push vendors to provide greater insights on DVR viewing and TV. At a meeting in October, Nielsen gathered its clients together to hear their concerns about TV and digital viewing measurements. For the most part, Nielsen’s clients have complained that the company has been moving too slowly on launching the single-measurement tool. Nielsen has also had to deal with reluctance on the part of its panelists, who were wary of adding a device to monitor their computing habits.