TV networks seek formula for online ads

The show, about two geeky physicists and their beautiful female neighbor, got 90,000 views on CBS.com and other Web sites over a week, followed by a better-than-expected 9.5 million for the Sept. 24 on-air premiere.

"The thought was purely to try to find new eyeballs in a medium that generally appeals to younger demographics, and then drive them to put butts in seats to watch on their beautiful plasma-screen TV when the series takes off," said Quincy Smith, president of CBS Interactive. "It was fairly radical, and we're happy with how it came out."

Looking to tap new revenue through online ads, attract new viewers and keep loyal fans, broadcast networks are making bigger, riskier bets on Internet delivery of their shows. The challenge is to grow viewership online without cannibalizing traditional ratings and DVD sales while making more money on programming seen on the Web.

But online audiences are still limited, a stumbling block that's expected to be a hot topic at the National Association of Broadcasters' annual gathering, which starts Monday in Las Vegas.

According to comScore Media Metrix, ABC.com led the network pack with 8.5 million unique visitors over its entire lineup of shows for the whole month of February, followed by NBC.com with 7.9 million. By comparison, a single episode of CBS's "CSI" recently took in more than 20 million TV viewers in one night.

Still, there are signs that the online experimentation will pay off.

Networks now charge more per thousand viewers online than they do over the airwaves, where the average for a primetime show is about $25. Analysts put the online rate anywhere from $35 to $50 per thousand, though there are millions more potential traditional TV viewers.

Advertisers pay more online because there is a better accounting of how many viewers see the ads and an extra benefit that an impulse to purchase can be acted on with the click of a mouse.

"For an advertiser, you're getting a clear performance result," said Bob Davis, a Web investor and former CEO of search engine Lycos. "No matter what the click-through (rate) they get, it's infinitely larger than the click-through they get on TV. The click-through they get on TV is zero."