Now I can help.
EVT is common terminology for a milestone in the hardware product development cycle:
Prototype units, Engineering (or Electrical) Verification Test (EVT), DVT (Design), PVT (Production), ramp. Design refers to physical design.
The above comments suggest the story: Fiona is Kindle 1, as you know. Turing is the hardware for Kindle 2 (Mario is the SW), Nell would indeed be another hardware device.
Fiona, Duke of Turing, Nell - all found on http://en.wikipedia.org/wiki/Diamond_Age