Robert Scoble, one of my favorite Microsoft apologists, continues to beat the tablet PC drum . He is, evidently, very happy with his tablet PC, and this this technology will be the Next Big Thing. Of course, Bill Gates said that several years ago, and it still hasn't happened. As Scoble conveniently points out in his article, shipments of Tablet PCs in the last 12 months were around 500,000 units.

That's about 1% of the total notebook market (50 million/year forecast for 2004), and somewhere around 0.3% of the total computer market. That's a fraction of Apple's market share, and very few people associate Apple's share with market dominance.

Anyway, what I really want to examine is what went wrong with the tablet PC? On the surface, it seems like compelling technology, so why has it been such a marketplace dud?

Let me begin by saying that I really would like something like a tablet PC. I used to own a gizmo called a CrossPad (which was also a complete bust), which was an electronic notepad in the literal sense. It held a pad of ordinary notebook paper, and when you used a special pen to write on the pad, it would capture an image of everything you wrote. You had both a hardcopy and an electronic copy of all your notes. I loved it. Very few others did. I could write a whole article on why the CrossPad failed (and maybe I will), but the point is that I have a soft spot for gizmos which combine the features of a notebook and a PC.

Despite my soft spot, I never bought a tablet PC. One reason was cost, another reason was the lack of compelling reasons.

But the biggest reason is that, to me, it didn't live up to the hype. The actual incremental usefulness of a tablet PC over a plain-vanilla notebook did not live up to the expectations which Microsoft's marketing department was setting.

Technology changes come in two flavors: evolutionary and revolutionary. Most changes are evolutionary. A better screen here, a nicer keyboard there, a bigger hard drive, better security, and so forth. But every now and then, a technology comes along which is revolutionary, and which fundamentally changes the way we do things. Revolutionary changes deliver order-of-magnitude improvements in cost, convenience, speed, size, or capability. Evolutionary changes build on what came before incrementally.

And the problem with the tablet PC is that Microsoft was promising a revolutionary change, but was delivering an evolutionary product. At its core, a tablet PC is basically a notebook with a flip-screen and a stylus. Now, I might really appreciate having a flip-screen and a stylus on my notebook, and I might even pay a few hundred more to get those features, but it won't fundamentally change the way I use a notebook computer.

So I, like (I'm sure) many others, looked at the tablet PC and basically said, "What's the big deal?"

And Microsoft said, "But it's a revolution in computing!"

And corporate purchasing departments said, "We're not spending $400-$800 more on our notebook computers."

And Microsoft said, "But it isn't a notebook computer!"

And IT departments said, "That flip-screen sure looks like a maintenance headache. I bet the hinges break all the time."

And Microsoft said, "But it will change the way you use your PC!"

And everyone said, "They just don't get it."

The irony is that there are some people who really love the tablet PC, and it really does change the way they use their computers. Those people, however, are a tiny minority. But if Microsoft had promoted it as a set of high-end laptop features, they may have gotten more traction, since people wouldn't have been disappointed when the evolutionary product failed to live up to the revolutionary hype.