In the mid-1960s, it was not uncommon for Captain Kirk's banter with the crew of the Starship Enterprise to be interrupted by a request to give his approval signature on a tablet. That's about as far as the show's writers took the idea but, as any visiting UPS delivery driver can show you, it proved prescient.
The greater promise of tablets as a replacement to mobile computers -- and even as a new kind of mobile information and communications device -- is starting to be realized in education and business.