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Disappearing from view is a good thing for the masses who just want things to work and don't want to bother learning how to operate something, let alone read a manual.
BUT! I think there should always be the option to thinker around. I don't mind an iPad being a closed system, but it would be a sad day if you were no longer able to build your own computer and install an alternative OS on it.
When things start to become simple and people expect things to "just work" it's not such a small jump to a situation where a government forbids any computer devices where users can "tamper" with, for they may interrupt services of the it-just-works-machines/systems/services.
The movie and music industry wouldn't mind that happening for it makes pirating less easy, nor would the government mind in their fight against terrorists, hackers and tax evaders.