FIVE YEARS AGO, producer Basil Iwanyk noticed that his TiVO was making some strange assumptions about the programs it thought he might like. His experience was chronicled in a front-page Wall Street Journal article, “If TiVo thinks you are gay, here’s how to set it straight.”

That story came to mind this week when NBC and CBS revealed their deals with DirecTV and Comcast to begin selling re-runs for 99¢, commercial-free and on-demand.

On the face of it, the movement toward on-demand TV seems to empower consumers, granting them the freedom to watch anything they want, whenever they want it.

But the personalization of broadcasting is a cultural phenomenon that’s being underwritten by a personalization of the advertising business — a trend that’s raising some sticky questions about the ways that marketers target consumers.

As the TV audience splinters, and as one-size-fits-all marketing goes bye-bye, advertisers are developing all sorts of invasive technologies to tailor their messages to a hyper-targeted audience. Some are collecting information about you that you’re not even aware of — and some of it is wrong.

VIRTUALLY EVERY MEDIA Web site identifies its users’ surfing history with cookies — tiny text files sent to your hard drive to track your online movements.

But cookies are easy to zap, so major Internet sites are rapidly developing other ways of tracking your activities.

Every time you perform a book search on Amazon.com, for instance, the e-tailer expands its profile of you. Its recommendations grow more targeted; it reminds you not to buy the same book twice; it even collects data on people for whom you buy gifts.

But as Web sites assemble ever-more-comprehensive dossiers on their customers, privacy-minded consumers are expressing grave reservations about the insidious social ramifications. Last month, more than 100 privacy advocates petitioned Defense Secretary Donald Rumsfeld to stop the U.S. military from developing a recruitment database including such things as student lists and motor vehicle records.

But such statistics aren’t hard to obtain with a simple Google search.

“The information that Google is collecting on all of us is staggering,” said Don Tapscott, a privacy expert who co-wrote “The Naked Corporation.”

“We leave this trail of digital crumbs as we go through life. As the Internet is the basis for work and learning and entertainment and health care, there’s the potential for the destruction of every form of privacy we’ve come to know.”

THE SALE OF NETWORK reruns through VOD or iTunes downloads won’t supplant traditional broadcasting any time soon. But major ad agencies aren’t waiting around to see what the future holds. They’re struggling to reinvent themselves for a world in which the 30-second TV spot becomes as antiquated an advertising medium as the radio jingle.

One day after NBC and CBS announced their VOD deals, Kevin Roberts, the outspoken CEO of Saatchi & Saatchi, delivered a blistering keynote on the state of the industry at the New York trade show called Ad: Tech.

“The only question you have to ask about any piece of communication is, ‘Do I want to see it again?’ Most television advertising in America I never want to see again,” Roberts said.

Ad execs like Roberts have an innate ability to discern opportunity in adverse circumstance. So it’s no surprise that at a time when people are talking about disintermediation — marketing jargon for cutting the ad agency out of the equation — Roberts would argue that the possibilities for plugging new products is multiplying — and that Saatchi & Saatchi has just the tools to do it.

“If you want your own band, your own record label, your own TV show, your own videogame or your own nightclub experience, we can do that,” he told the Ad: Tech crowd. “But we’ve got to move from permission to attraction. The principle of permission marketing is you ask consumers. With attraction marketing, they’re gonna come looking for you, again and again and again.”

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