In just a few hours I will be on stage keynoting Forrester's eBusiness and Channel Strategy Forum: Seizing Opportunity From Digital Disruption. This is an exciting event because it was one year ago at this same forum that I debuted our research on Digital Disruption, to overwhelmingly positive response. 

It's now a year later and a lot has happened. Digital Disruption will soon be available as a hardback book (also as an eBook, natch). You can pre-order a copy now at Forr.com/DDbook. To complete the book I had to get far outside of my comfort zone — I work with media companies and consumer product companies primarily, but to prove that digital disruption is a fundamental change in the way we all do business, I had to interview people in the pharmaceutical industry, the military camouflage industry, and I even recently spoke to the CIO of a cement manufacturer! And to my pleasant surprise, they were every bit as digitally disruptive as their counterparts in the consumer-facing enterprises that we think of when we imagine digital disruption.

One of the main reasons every company can be and eventually must be a digital disruptor is the rise of digital platforms. These platforms are founded on a set of devices, wrapped together with software experiences that identify each customer individually, and are open to app contributions from thousands of partners. The platform owners that matter today are Amazon, Apple, Facebook, Google, and Microsoft.

There are several contenders that would like to be platforms but are not currently. Samsung is a good example — its devices are very good; they'd have to be or Apple wouldn't resort to suing Samsung to suppress them. But Samsung's devices don't create a single customer relationship experience that accrues back to Samsung. I applaud the company's radical moves like the recent jump into low-cost Chromebooks. But there again, the crucial digital customer relationship belongs to Google, not Samsung.

Comcast is the other big player with platform ambitions, but the road to platform-dom is even longer for Comcast because even though it's big, it's not even truly national, much less a global player, and therein lies the rub: Platform power derives in part from platform scale. There is a longer list of potential platform players, one of which is Sony, about which I'll have more to say in the virtual pages of The Economist's Lean Back 2.0 blog soon. But suffice it to say that Sony had all the ingredients needed to be a platform in about 2007. However the company never left its obsession with engineering behind in order to turn toward this new model and, as a result, just announced the layoff of 10,000 more employees around the globe.

Which leads to Apple. Apple was one of the first platform players to matter. Its iPhone (and the nearly accidental embrace of the App Store idea a year later) created the conditions on which Apple is now a raging success. The iPad — which Apple just announced crossed the 100 million threshold this past quarter — would have sold a fraction of that if it didn't have the App Store, bringing with it thousands of developers who add most of the value to the device, no matter how elegant and sleek it stands on its own.

The real power of platforms like Apple's is not just manifest in the large number of units shipped. Instead, it's in the range of things people do with it. In our consumer surveys we routinely find that people use their tablets — the majority of which are iPads today — to do dozens of different tasks each month, and personal experience suggests each day. There is no other device that has achieved that kind of multipurpose utility (see my post on The Economist about Swiss-army gadgets for more on this). And because Apple ties the experience to its laptops and phones and even its Apple TV, the company builds on its relationship with you to get you to use all of the devices more often than you did before. There is no precursor to this in the world of industry. Massive industries — like the railroads that rose up at the dawn of the industrial age or the burgeoning healthcare industry that is taking over so much of our economy — these were or are big businesses, but none of them ever built a platform for expanding customer use and dependence like today's platform companies.

That's why I refer to these platforms in nearly every speech I give and why I'll be talking about them in a few hours on stage at the Forrester Forum. Because these platforms will be necessary foundations on which your business — whether you develop apps or manufacture cement — will have to depend. Companies ranging from Monsanto to GM have given into this pressure, with both of them tapping thousands of developers to improve their internal businesses as well as their product experiences by tying into these platforms.

That's why it matters that Apple has reached 100+ million iPads shipped. Because it's the clearest proof I have that platform power is now the central power in the business world. But it's only the beginning, and you had better join.