(FORTUNE Magazine) – The postwar history of American advertising, like the postwar history of pretty much everything, can be divided into three stages. First came the Age of Innocence, in which people who made ads drank Scotch, wore suits, wrote jingles, and had ulcers. That age was sufficiently cataloged by MAD magazine and Bewitched, and you will hear no more about it. The Age of Influence commenced when advertising people started drinking Perrier instead of Scotch, began talking about cinema verite, and became comfortable with the notion of "hanging" with Spike Lee. This golden age lasted until about yesterday, when they all suddenly stopped talking about cinema verite and started talking about clicking the whatsit on the whosit to buy the thatsit from the comfort of your living room divan, thus ushering in the Age of Ambivalence.

Advertising right now, Madison Avenue types say, is on the brink/verge/threshold of a revolution. That revolution has something to do with the major networks' falling share of the television audience, something to do with people being tired of obvious "selling," and something to do with TiVo. Before it had something to do with TiVo, it had something to do with "Jennifer Aniston's sweater." As in, you'll be watching an episode of Friends, and with one click of your remote control you'll be able to buy Jennifer Aniston's sweater. But now that the technology to do it has been around for a few years and nobody has evinced the least bit of interest in buying Jennifer Aniston's sweater, people have stopped talking about sweaters and started talking about personalized ads and downloading movies and fast-forwarding through commercials on TiVo.

You might think that the prospect of people skipping commercials, combined with the prospect of the networks withering on the fiber-optic vine, combined with "advertising fatigue," might give ad people chills. If you think that, you are not an advertising person. Sure, ad people will often talk about how the big, glossy, 30-second ad is becoming obsolete. But when you probe further, it turns out that what they mean is not really that commercials will disappear but that those pesky television "programs" that surround them will. "Eventually there will be entire channels devoted to commercials," speculates DDB Needham Chairman Keith Reinhardt. "It's all just content!"

The makers of ads truly believe that people watch TV just to see the commercials; ad guru Jay Chiat asserted earnestly in Time magazine that people who watch the Super Bowl are "interested in the game but even more interested in the advertising." That would be totally unbelievable except that while recent TV is spectacularly bad (is Fox really airing a boxing match that pits Paula Jones against Tonya Harding?), recent commercials have been spectacularly good (DDB Needham's "Whassup?" campaign for Budweiser, Nike's coolly futuristic "Tag").

Commercials have gotten so good because while in the Age of Innocence ads had to sell stuff, and in the Age of Influence ads had to sell stuff in an arty way, contemporary ads have generally been liberated from the obligation to sell stuff at all--or at least to sell stuff in any way that the audience is going to view as "selling." Says Rob White, president of ad agency Fallon Minneapolis: "It is hard for advertisers to assume that anything they say is going to be believed. Advertising as a source of rational communication hasn't been successful for some time now." In other words, ads can't tell viewers about products anymore because nobody trusts what they say about products, so they're free to be just really good ads. And our willingness to buy products becomes a sort of referendum on the commercials.

Bet on the trend continuing, with tomorrow's advertising becoming increasingly Zen-like in its abstention from any connection with products. Budweiser ads are about "Budweiser," not about beer, and Nike ads are about "Nike," not about sneakers. Does this mean that as advertising becomes product-free you'll be happy to watch 500 channels of program-free advertising? Don't count on it. Great advertising today doesn't exactly resemble the great advertising of earlier years ("Oh, what a feeling! Toyota!"), but it doesn't exactly resemble programming either. Tomorrow's advertising will be the same, only more so. Think of it as an almost subliminal Third Way. A new kind of ambient short-form entertainment--which happens to make you really, really want to buy sneakers, minivans, and corn chips.

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