What's not yet known is whether there is a direct link between the online usage and the viewing patterns.
WHAT MAKES STUDY NOTABLE
While such studies have been attempted before, the AOL-Nielsen survey marries data from the nation's largest online service with TV viewing information gathered by the most influential TV measurement company.
Neither AOL nor Nielsen would talk about the survey; initial results are expected to be announced in the coming weeks.
But executives familiar with the study said Nielsen, at AOL's behest, cross-referenced its 5,000 national people-meter homes against a list of some 10 million current and former AOL subscribers. Close to 500 of the households matched, according to one executive.
AOL and Nielsen are expected to release a number of specifics, such as how much viewing of specific TV networks is done by the AOL households compared to other households. But, despite Nielsen's access to historical data to compare viewing in homes before and after they subscribed to AOL, the companies will not draw any conclusions about a cause-and-effect relationship.
"Since AOL homes are generally upscale, that could be the factor that determines the amount of TV viewing, since we know upscale homes watch less TV," said one of the executives familiar with the survey.
In the future, Nielsen hopes to be able to make direct correlations between online usage and TV viewing. To facilitate that kind of a finding, the company recently began asking those who participate in its sample to keep track of their PC usage.
Further, Nielsen would like to hook up with more Internet access providers and online services to get a more complete picture of online usage.
One phenomenon that clearly needs more study is the impact of online usage on kids' TV viewing. Nielsen has come under fire for what the networks claim is under-reporting of kids' TV viewing. But some claim kids' viewing is indeed down, and that at least some of that time is spent online.