iPad design principle is a diametrically opposite to the Apple Computer's founding one

This article by Johnathan Zittrain provides a timely warning of the danger of allowing Apple to exert such a tight control on its recently released products, namely iPhone and iPad. He provides a historical account of how Apple Computer was established based on a computer, Apple II, renowned for its ability to be reconfigured almost infinitely with third parties parts and then contrasting its recent diametrically opposite corporate view - Apple controlling everything.

He reminds us

If Apple is the gatekeeper to a device’s uses, the governments of the world need knock on the door of only one office in Cupertino, California – Apple’s headquarters – to demand changes to code or content . Users no longer own or control the apps they run – they merely rent them minute by minute.
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Mr Jobs ushered in the personal computer era and now he is trying to usher it out. We should focus on preserving our freedoms, even as the devices we acquire become more attractive and easier to use.