I would extend Tim's comments to include voice and speech as modes for interacting with computers. My wife and I got new Android phones recently and we both adapted instantly to speaking commands as often as possible instead of using the touch screen. For low bandwidth output, speech generation is good also. But in the large sense Tim Bray is right: text may be low bandwidth in a Shannon-sense, but is high in information bandwidth. As an example, I got more out of a 5 minute read of the New York Times online newspaper this morning than 30 minutes of watching any news show that I can think of (even the Colbert show :-)