"There were arguments about picking other technologies such as streaming video or whatever, but we picked HDTV because it is in so many homes now, and is really impacting the way people are watching television, which is still the most dominant medium," said David Tice, vice president and group account director at Knowledge Networks.

Tice noted the adoption of HDTV changes the "choice set" of the channels TV households tend to watch. While the average TV household generally watches only about a dozen of the 100-plus channels they typically receive on a regular basis, Tice said HDTV households tend to shift their viewing preferences from channels offering low resolution fare to high definition content.

"About a third of people who get HDTV says they go straight to the HD section of their programming guides," Tice said, adding, "Channels that don't have HD are at a bit of a detriment, because they're not the first choice."

Tice said HDTV households also tend to plan their viewing ahead of time more than people in households without HDTV.

According to the most recent Knowledge Networks estimates, about 28% of U.S. TV households now have HDTV, up from 20% last year, and Tice said it is being driven largely by households upgrading their television sets in anticipation of the conversion to digital broadcast spectrum early next year.

"It's pretty hard to buy a new TV set and find one that is not HD capable," he noted. As for whether new HDTV households are actually receiving HDTV reception via cable, satellite or terrestrial signals is another matter, but Tice says Knowledge Networks' research indicates that two-thirds of HDTV households claim to also have HDTV reception, up from about 60% lasts year.

"I'm shocked," quipped Mark Cuban, the president and co-founder of HDNet, the high-definition television network and producer that has been pioneering the field for about eight years.

Cuban said he also is hearing anecdotal evidence that HDTV is impacting the way people watch television, especially high-profile sports programming such as NBC's coverage of the Summer Olympic Games.

"I'm hearing that the Olympics are up 25% in homes with HDTVs," he said, adding that the number is even higher among households with HDTV programming reception.

Knowledge Networks' Tice, meanwhile, said the impact of HDTV ultimately will transition to normalcy as it becomes more of a standard for transmission and programming, much the way color TV did in the 1960s. But for now, he said, it represents a competitive advantage for channels, programmers and advertisers who have embraced it.

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