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Computing technology reaches it's apogee when it disappears from view, when the user of the technology is not aware of the technology being used and they are only aware of the task being undertaken. All good technology should vanish from sight, the more in sight it is, the more the user has to think about the tool and not it's function, the worse the tool is.
Smart phone technology is a big step forward. You tap an icon and speak to someone, or dictate some text which someone else can read, anywhere in the world. You approach a location and the device gently reminds you to do something, you tap an image and a flood of information is available, you see something and instantly capture an image of of it.
As fantastic as smart phones are they still require too much thought to use, they still get between you and the activity or function. There is still a way to go yet.
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.