One of the cool things may well be that wifi "cells" grow-up organically -- a coffee shop here, a pub there, maybe a few apartments sharing their connections via FON...

I actually don't think anybody could deliberately build such an infrastructure. Like the Internet itself, it has to grow organically -- it will be a network constructed and utilised by the people who created it. Other deliberate corporate attempts to build similar systems, such as Rabbit here in the UK, have failed (see http://news.bbc.co.uk/1/hi/technology/2175804.stm).

When I think about things like this, I realise even more how powerful the Internet tablet concept is.