FORTUNE — First there was Comdex, ostensibly a computer-industry buying exposition in Las Vegas that nevertheless became an annual party for all of Silicon Valley. Then, when Comdex collapsed with the dotcom bust, the already-existing Consumer Electronics Show, ostensibly a gathering of device makers showing retailers what they could sell the following Christmas, surged in importance.
CES, like Comdex before it, was mostly a geekfest. It was the place to see the latest gadgets — some real, some so fantastical that they’d never see store shelves — designed to set the hearts of gearheads aflutter. It also was an opportunity for a few clever companies to launch major products and to grab the attention of the personal-technology press. A breakout hit at CES could define an entire years of sales.
Then something changed. Product launches diminished in importance. It became too hard to get noticed, and Apple (AAPL) taught manufacturers that it’s much better to do your own event than to compete for attention in Las Vegas. Yet CES is stronger than ever, the undisputed nexus for opinion leaders in any industry touched by technology to come together right after the new year. Any topic remotely tangential to technology is fair game in CES, from air conditioners to automobiles. A few years back it even became a venue for Gary Shapiro, president of the Consumer Electronics Association, which puts on CES, to hawk a book promoting his own brand of Democrat-bashing free-market politics.
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Indeed, for all the action on the show’s many floors — walking all 1.9 million square feet of CES is a soul-sapping, dehydrating, physically grueling, thoroughly demoralizing experience — as much action happens off the floor as on. CES even has become an important stop on the circuit of chief marketing officers, who are fully aware that technology holds the key to their future. (Shameless plug: This week, I wrote about a panel my colleague Jessi Hempel moderated at a Fortune event during CES. It focused on digital marketing.)
In fact, a chief marketing officer who doesn’t attend CES runs the risk of being out touch. “Marketers who come to CES now aren’t here to see the technology per se,” says Wenda Millard, who runs the digital marketing advisory firm Medialink. “They’re really here to understand technology as a facilitator of changes in consumer behavior. They’re not looking at technology because it’s cool. They’re looking at changes in consumer behavior caused by changes in technology.”
To reduce it to a business cliché, CES has achieved critical mass. And then some. “CES is the Burning Man of digital transformation,” says Neil Ashe, the head of Wal-Mart’s $13 billion — but money-losing — e-commerce effort. (Shameless plug number two: I interviewed Ashe Monday night in Las Vegas, and he’s the one who pointed out that Wal-Mart (WMT) doesn’t yet make money online.) Ashe adds: “On the consumer side, it is a great place to go to be immersed in what consumers are going to be experiencing over the next couple of years. On the business side, the bigger it has gotten the more important it has become as a gathering point. It was interesting to see the diversity of floor participants this year. Some of the usual participants are gone or smaller [e.g. Microsoft –Ed.], and you have the New York Times, United States Postal Service, and BMW taking over the whole parking lot. It’s amazing how it has evolved.”
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To its credit, CES has thrived despite not even delivering on one of its key selling points. “In the last five to seven years it has become as much a sales and marketing event as a geekfest with the brightest TVs,” says Bob Borchers, the newly installed chief marketing officer of Dolby Laboratories (DBL). “It’s been a steady evolution. Now it’s as much a place to meet and be visible as an announcement stage. There’s always been so much noise. It’s a challenging place to launch new idea. But a great place to meet.”