Pfftt.... 1974? Dumbfounding that people find his parroting of Charles Babbage's ideas from 130 years previous in any way insightful. http://en.wikipedia.org/wiki/Analytical_Engine
Also, Doug Englebart already had a working demonstration of this tech in 1968, almost a decade previous, commonly referred to as "The Mother of All Demonstrations" - (http://en.wikipedia.org/wiki/Douglas_Engelbart
you can view the demo here - Douglas Engelbart : The Mother of All Demos (1/9)
), so how is anything Arthur Clarke was babbling on about at the time in any way prescient?
This would be like Michael Crichton saying 10 years from now "Someday everyone will have a mobile computing device that fits in their pocket, and you could touch the screen to make it do stuff" ...YOU DON'T SAY?