NBC and cable networks led by USA “were trading at a 20% discount to our competition” in the cost-per-viewer of ad sales before the recent upfront market, NBCU chief Steve Burke told analysts this morning. “We’re now at about a 10% discount.” Comcast‘s entertainment arm says it bucked a trend in the upfront — seen as generally down 5% vs last year — as it benefits from the growing popularity of its shows, and a decision to sell broadcast and cable ad inventory together. “If the industry was down 5% and we were up 10%, that’s a 15% difference vs what we would have done” if NBCU had sold broadcast and cable separately. “It’s a swing of $750M” that will go “a long way toward closing monetization gap.”

Burke doesn’t believe that traditional TV networks were hurt by digital video providers including YouTube, Yahoo, and AOL that lobbied advertisers to shift dollars away from TV. “Ad agencies decided to be less aggressive” in the upfront market. “They will show up in scatter. We may be wrong. But that’s our analysis….If scatter is strong, this could be a good year for advertising.”

In response to a question about AT&T’s planned acquisition of DirecTV, Comcast CEO Brian Roberts — who has agreed to buy Time Warner Cable — says it’s “a very powerful combination and it validates the changing and dynamic nature of the market.” Still, regulators “have to look at each situation differently and individually” — and, he noted, in his deal with TWC “we do not overlap in any market, hence there’s no diminishment in choice.”