Big Data has reached a tipping point. It is now officially the hot new technology industry of the second decade of the 21st century. And there were 70,000 witnesses to the moment it happened.

How do you know when a new technology becomes cool? When everybody who is anybody in tech feels obliged to attend its trade show.

Old Silicon Valley veterans will tell you that this has been the case for at least forty years – and perhaps even longer. For all I know, there were must-go mainframe computer shows in the 1950s, and I’ve heard that there were vital semiconductor and minicomputer conferences in the 1960s. Certainly in the mid-1970s the West Coast Computer Faire – Westcom – in San Francisco was an absolute necessity. . . especially after the newly founded Apple Computer showed up with the Apple I, and most famously, the Apple II.

By the end of the decade, the torch had passed to the Consumer Electronics Show (CES), which for a decade reigned as the place to see all of the new consumer tech, from PCs to games to porn. Within a few years, however, the zeitgeist had shifted to the Internet, and with it to Comdex – perhaps the high water mark of tech industry trade shows.

In time, CES stole the mantle back – and it still reigns today as the industry’s biggest omnibus show. But other, more focused, industry gatherings began capturing the spotlight.

The most famous of these, of course, was MacWorld, with its now-legendary new product announcements by Steve Jobs. But there were other important shows as well — less noticed because they were less consumer-oriented – including those dedicated to security, mobile and digital infrastructure. For the last one, the dominant industry gathering for years now has been Oracle Open World. And it has been surprisingly enduring, dominating the world of servers, databases and enterprise computing now for two decades.Until this year.

For the first time in the memory of most people in the enterprise computing and software business, Oracle Open World took a back seat to a whole new industry event, this one dedicated to the Cloud and to Big Data. It was called the Dreamforce Show, and as the name might suggest to anyone who hasn’t yet heard of it, it was sponsored by – and in particular, that company’s flamboyant founder Marc Benioff. Last year’s show seemed like little more than three guys and a dog; this year looked like the tipping point of a new technology revolution.

If Salesforce’s name was on the title, and Benioff was again the keynote speaker, the reality of the show was much, much bigger. Dreamforce has quickly become the official gathering of the tribes in the world of Cloud Computing. . . and the most common question asked in the Valley that week in mid-September was “Are you going to Dreamforce, too?” And, in my experience, the answer was universally, “Yes.”

Walking into Moscone Center in San Francisco, I was reminded most of Comdex in the Nineties. Seventy-thousand people, scores of expensive exhibits, and most importantly, an intriguing mix of ambitious start-ups (Marketo, Elequo, and the slightly older Box and Okta) with giant corporations such as General Electric and Virgin America. This kind of combination of big and small, new and old, hungry and rich is what characterizes dominant trade shows at their peak; it rarely lasts more than a few years, after which they are typically dominated by a few big players.

Dreamforce also had a lot of the fun traits of a super-hot trade show. One is the appearance of celebrities and business superstars – such as Richard Branson, one of the keynote speakers, and even Tony Robbins – and the mainstream media, which came out in droves.

Another hotness indicator is the presence of those companies that have nothing to sell this year, but knowing they need to have a high profile at the show, substitute hype (usually crazy marketing stunts) for real products. As they whip themselves in hysteria, you can almost smell the flop sweat. There were a lot of these companies this year, caught flat-footed by the explosive growth of both the industry and the conference. And many of the hype artists were the big old enterprise companies, struggling to stay in the game, and hang on to their loyal customers, until they can come up with a competitive response to the newcomers.

Interestingly, for all of the excitement, this year’s Dreamforce theme was surprisingly retrograde. Benioff declared it the year of social networks – not the Facebooks and other Web 2.0 companies, but the adoption of social networks as social relationship tools between large enterprises and their customers. As my fellow Forbes blogger Victoria Barret has noted, an estimated 70 percent of all large enterprises in the U.S. have now “adopted social” – and thus these tools, and the Cloud in which they reside – has become a very lucrative market for suppliers like

All well and good, but choosing that theme also gave Dreamforce a touch of anachronism – of being a bit behind the curve – that didn’t match the current enthusiasms of the legions of attendees. I’ll admit to a bit of bias, but my impression was that most of the attendees were there not to talk social networking, but Big Data and the analytical tools that make it possible. Almost universally, they know that is the future of the Cloud. . . and they want to be there.

As for me, and the rest of us in the world of analytics, this year’s Dreamforce was a vindication. For years we have been predicting that the Cloud, business analytical tools, and Big Data would combine to change the world of information and our relationship to it. Now, it’s here –and the best marker for that arrival is the ascendance of Dreamforce to the top of the trade show pyramid. We’ve arrived – and now the challenge will be to build an ecosystem in Big Data healthy enough to attract the adoption by established enterprises, just as social networking has now done.

So don’t be surprised if Marc Benioff’s theme next year is a celebration of Big Data. If it isn’t, Dreamforce’s dominance will be short-lived.