US television gurus are finding it difficult to quantify the real impact of digital video recorders on TV advertising.

Advertising executives who heard the presentation by CBS TV network vp David Poltrack to the UBS Media Week Conference, were comforted by his company's research. It finds DVR viewers who skip ads can still recall, on average, two commercials and one brand, a not dissimilar result to live TV viewers.

Poltrack also opines that DVR use will add to audience ratings, doubling the numbers for the most popular network shows.

But just as media folk think it safe to venture back into the murky waters of TV advertising, a new alert can be heard.

Steve King, ceo of ZenithOptimedia, warns that ad-skipping technologies such as TiVo and DVRs are cutting into commercials viewership and forcing advertisers to seek other media.

Says King, enigmatically: "It does seem television has reached a stage of maturity."

Data sourced from; additional content by WARC staff