What year was the tablet? Samsung argued against Apple that they couldn't own the design of the tablet itself because it had been done in 1968 in 2001: A Space Odyssey. Either way, nearly every piece of tech could probably be found first in sci-fi.
Dang, I actually would like a Write-Top, and this technology at that point is impressive to me:
Using an advanced symbol-recognition algorithm, the Linus ("of or about lines") can convert your scrawls into perfect text at a rate of about 5 characters per second. It recognizes uppercase, lowercase, numbers, and symbols.
I'm sure modern tablets can do that even better but I haven't used one I really like the feeling of while writing.
*EDIT: Weight: 9lbs / 4 kg I change my mind, modern tablets are where it's at