Mature markets thrive because of specialization, not in spite of it. Think of shoes. How many pairs do you own? How many do you really need? Or kitchen pots. How many pots do you own? How many do you need? Or cars. How many different types are out there? How many do we really need?
The answer is, as many as they want to make. We want specialty shoes because there's a real difference between road biking shoes and mountain biking shoes. Between brown shoes and cordovan shoes and black shoes. Between dress shoes and party shoes. And those differences matter. Riding 35 miles in your dress shoes makes no sense.
And we want the best pot for the polenta or risotto or Bolognese we're making. We want the car that best suits the way we drive and live and schlep stuff. We want the right tool for the job. The same is true for computers or tablets or smartphones. We want the right tool for the job.

Source: Hallomall.com
When you show me a spork or a rubber soled dress shoe or an El Camino, I think, "that's neither spoon nor fork, neither practical nor dressy, neither car nor truck." So when you show me Windows 8 on the new Dell XPS 12, I think spork, not specialized. It's a straddle. And straddles don't win.
The future of devices (call it post-PC if you like; I just think of it as the right tool for the job) is specialized: the right tool for the job, and a steady evolution to the right tool. The logic is simple:
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