“The problem is the same as in every gold rush: the gold is easier to see than to mine,” said Lindsay Conner, a lawyer at Manatt, Phelps & Phillips who specializes in entertainment finance. More serious financing is starting to trickle in, he said, “but we’re a ways away from truly cashing in on either the cost-saving or revenue-generating potential of the Internet for entertainment.”

Jordan Levin, chief executive of Generate, a digital production and distribution company, was more blunt. “Ad dollars are coming back, and digital deal-making may be quickening,” Mr. Levin said. “But it’s not enough to fuel a robust and dynamic market, and by that I mean a market that isn’t just a bunch of meaningless announcements.”

Start-ups, many of them self-financed, see it quite differently.

“We think we are reinventing television,” said David Levy, C.E.O. of Philo, a month-old social networking service that lets groups of people interact while watching television. “More people understand this time around that you have to have a serious idea,” he said. “Just because the barriers to entry are so low that anybody can start a company doesn’t mean that just anybody should.”

Technology is increasingly ripe for this kind of experimentation, says Larry Kramer, founder of MarketWatch.com and author of the forthcoming book “C-Scape: Navigating the Rapidly Changing Worlds of Media and Business.” He noted that Apple’s iPad and the rush by networks and movie studios to be a part of it  ABC was quick to offer 20 shows for iPad streaming  created a burst of activity by themselves. Internet-equipped television sets are also becoming more mainstream.

And digital sales of movie and TV shows continue to grow. The Digital Entertainment Group, a trade organization, said the category generated $1.1 billion in the first six months of the year, up 23 percent from the period last year. Most of the successful digital entertainment companies operate in this area, including Netflix, which recently said that use of its streaming service was running double last year’s rate.