Intriguing to think that certain urban forms make certain digital formats more viable.
“For many skeptics, imode-type services will never take off in the U.S, for one simple reason: the car. In Japan, the ubiquitous mass transit system is often cited as a primary reason for imode’s success. The transit system creates a lifestyle full of “microniches” of time. There’s a lot of hanging around nearby bus, subway and train stations, usually waiting for friends or for transport. Imode and its competitors have filled this otherwise empty space with well-received services and cutting-edge handsets…”
Petafloptimism 
The other interesting point about i-Mode is that Japanese can be typed one fingered more easily than English (all the characters are a combination of five strokes, I think) – and that actually talking on your phone on Japanese public transport is illegal: so people have to use the i-Mode bit if they touch their phone at all. Plus most of the Tokyo tube system is above ground, where there is signal.
interesting yes, but the statement that i-mode (or equivalent) won’t take off in US cities as they’re car-oriented is a little strange (as the Salon article points out, in fairness). many US cities are not any more car-oriented than, say, birmingham (uk). and given that 75% of the world’s population will live in cities by 2020 (inc. the US, where Mike Davis’ excellent book “Magical Urbanism” notes new urban forms which are essentially not car-based at all, but ‘classically mediterranean’ in origin), i think a richer view of city life is needed here. the notion that all US urban residents do is sit in traffic is a bit simplistic. many US cities are extremely walkable, with highly-used public transit systems. sounds like non-urban space may be essentially more car-oriented …
however, it is interesting to think how urban space/time flows affect devices – if there are predominantly car-based ‘microniches’, perhaps i-mode can be modified via voice-interface (flawed, i know) – but then ben’s point about single-finger operation may be relevant here too.
Aren’t traffic jams themselves a microniche?
It seems like you’ve got a network of sorts waiting to be exploited here.
OK, it might be an involuntary one (like a doctors’ waiting room), but it still permits communcation, even if only through the car horn.
We just need to build a richer communication device than the horn, then we can unlock this social capital…
Or maybe not.