Sure, the internet and cable are siphoning off viewers, the slowing economy threatens to crimp revenue, and the writers' strike has interrupted program production. It'd be easy to write off TV as the world's primary ad medium.

Easy, but perhaps premature.

You'd hardly have considered the idea at the Upfronts last week in New York, where network executives presented their fall schedules to advertisers. While the week was more subdued than in years past, and there were plenty of references to digital and mobile ad platforms and the devastating writers' strike, the overall mood was upbeat and exceedingly pro-TV.

"More and more consumers access content in many ways," Jon Nesvig, Fox's president of sales, said at his network’s Upfront on Thursday. "But viewers still choose to view the majority of their content on TV sets." For every minute of TV or video that people stream online, he asserted, they still spend 14 hours in front of their TV's.

Fox's presentation was followed by a lavish party at the skating rink in Central Park, where Kiefer Sutherland and other network stars posed for pictures, pomegranate-champagne spritzers made the round on silver platters, and guests were treated to enormous buffet spreads of sushi, hamburgers, and Brazilian churrasco.

It was hardly a snapshot of an industry poised on the brink of ruin.

Of course, broadcast-television audiences are thinning. But analysts point out that the viewing audience for television in general—including basic and premium cable channels—is growing year over year. That's good news for conglomerates, like General Electric and Disney, that own cable channels along with traditional broadcast networks.

"The new silver bullet that's going to overtake TV hasn't emerged," Lee Doyle, C.E.O. of Mediaedge:cia North America, a global communications company, said. "As much as consumer behavior is changing, TV remains one of the most powerful marketing tools to have."

That doesn't mean, of course, that networks aren't embracing digital innovations. Last week, executives from ABC, CBS, NBC, and Fox all emphasized a willingness to offer advertisers new platforms to reach viewers.