Los Angeles ? With “American Idol” and Jay Leno back on the air in January, it may seem that all is right with television. But the industry is facing its worst labor crisis in two decades, a crippling writers strike that’s reshaping the business of TV and threatening to permanently shift the viewing habits of millions of Americans.

Now in its seventh week, the Writers Guild of America walkout has forced producers to reconsider how shows are developed, the type of shows produced and how they’re sold to advertisers.

On the audience side of the equation, a flood of strike-induced reality series and truncated dramas may drive viewers toward alternate entertainment – including Internet programming, which is at the heart of the contract dispute.

The walkout has halted production of most scripted and late-night shows, although Leno and Conan O’Brien are coming back to work next month on NBC, as is ABC’s Jimmy Kimmel. CBS’ David Letterman was considered likely to follow suit.

Talk of industry change is dismissed by some writers as spin designed to undermine union resolve on payment for streamed and downloaded distribution. But networks contend the strike has given a new urgency to the need to confront ballooning costs and an evolving marketplace.

“The strike is forcing us to look at the way we all do business and to make choices that were tough when business was as usual,” said NBC Universal Chief Executive Jeff Zucker. “This is allowing us to make the tougher choices.”

Pilot season

With negotiations at a standstill, the impact is extending to the 2008-09 season, beginning with the typical first-quarter “pilot season” in which networks commission single episodes of potential series.

It’s an unwieldy process that may have had its day, said two executives at a major network, speaking on condition of anonymity because their company had yet to officially detail its plans.

Pilots are more expensive than ever to produce, reaching $6 million or more for complex action dramas, but don’t necessarily represent the series that are delivered, the executives said. This year’s results were unimpressive, with a number of anticipated new series – ranging from NBC’s “Bionic Woman” to ABC’s “Cavemen” – failing to get ratings traction.

Instead, networks are considering taking pitches straight to series, especially when a show comes from road-tested producers. A prolonged strike would force the issue, pushing broadcasters up against the fall season production deadline.

Another entrenched custom involves May events in New York at which networks, with elaborate, multimillion-dollar fanfare, unveil their fall schedules for Madison Avenue and collect billions of dollars in advertising commitments.

“There has been no final decision, but it is increasingly unlikely that we will do a traditional upfront presentation this year,” CBS spokesman Chris Ender said. “We’ve been talking about it for years; this may be the opportunity to work with our clients to reinvent the process in a way that better serves networks and advertisers.”

NBC is reconsidering the scope of its presentation, Zucker said, but added, “I don’t think the selling period will change” because of its efficiency.

Audiences left out

For audiences, the central issue is loyalty amid disorder.

Because of the strike, “Lost” may only be able to air half the episodes of the 16 that were planned when it returns in January. “Desperate Housewives” won’t reveal the second part of a tornado cliffhanger until after the drama resumes production.

A few new scripted shows are poised to help fill the gap, and other options are emerging, some innovative. NBC said this week it will air “quarterlife,” an Internet series from the producers of “thirtysomething,” with short “webisodes” combined into hourlong episodes.

At least one network is taking a look at imported programming, mulling how receptive U.S. viewers would be to shows lacking an American accent.

But upcoming broadcast schedules largely will be stuffed with reality shows – and not just blockbusters like Fox’s “American Idol,” or ABC’s “Dancing with the Stars,” which returns in March.

If the genre doesn’t burn itself out, the programming balance could remain tilted toward reality even after the strike is settled.