"This is pretty transforming," said Forrester analyst Charlene Li. "The other networks are going to have to follow their lead unless they want to lose viewers and ad dollars."

Key national advertisers--including AT&T Inc., Ford Motor, Procter & Gamble, Universal Pictures, and Unilever--have already signed up to accompany free, full-length episodes of ABC's "Lost" and "Desperate Housewives," the morning after they air on TV. The shows will be available at ABC.com in May and June, initially.

Those and two other shows--the low-rated "Commander in Chief" and "Alias," which will end its five-year run next month--will become available on April 30, upon the relaunch of ABC's Web site. Other Disney Web properties--Disney Channel, ABC Family--are expected to start offering full-length programming by the summer. Viewers will be able to pause, rewind, and fast-forward the new and archived episodes, but advertisements embedded within the programs can't be skipped.

Sweeney on Monday emphasized the sustained power of established brands in an increasingly fragmented media universe. "In the future, consumers will rely more and more on strong brands to help them navigate the digital world, and we have some of the strongest brands in entertainment," Sweeney said in a statement. "Our digital media efforts will help us strengthen our connection with our consumers."

Now--before the Web really begins cannibalizing TV networks--is the ideal time for Disney to perfect its Web strategy, said Jupiter Research analyst David Card. "It's a big deal what they're doing," he said, "establishing themselves online before the real cannibalization begins to occur."

The Disney-ABC Television Group recently announced that full episodes of original series from the Disney Channel and Jetix--the action-programming block that airs on Toon Disney and ABC Family--would be offered up online before the summer. If all goes according to plan, young visitors to DisneyChannel.com and Jetix.tv will be able to stream full-length episodes of popular shows like "Kim Possible," "Power Rangers," "Super Robot Monkey Team Hyperforce Go!" "That's So Raven," and "The Suite Life of Zack & Cody," among others.

Disney also announced plans to launch a soap opera broadband channel, dubbed Soapnetic, on April 17, but initially only for subscribers to Verizon Communications' Internet services.

Disney has led the way in experimenting with new content delivery platforms; ABC was the first network to sell episodes of its hit series for $1.99 each on Apple's iTunes music store.

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