The Glass opens up tremendous opportunity for Google to perceive the behaviour of each user in far detail than possible now. This means, an unprecedented access to more of our human - to - human time. When the interface becomes invisible as in the Glass, there is very little a user can do to decide on the appropriateness of the content that gets communicated and shared. The interface is becoming a part of our real self. I will not be surprised if when using the Glass and playing a game of tennis, my Glass realises that I am poor in the sport, and superimpose training videos on my retina followed with advertisements of training institutes.
This is scary thought, but one whose time has come. I am all excited and scared at the same time :)
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