The title should say it all but here's a funny little video that sort of shows why programming will likely stay keyboard based at least for the near future:
http://gramatan.livejournal.com/46533.html
Good god, 10 minutes and he's got four (or was it five?) very simple lines of code written.
I know it was meant to be funny. Speaking code is probably never going to be as efficient as typing it.
I bet it would work fairly well on case insensitive languages that use English syntax such as Pascal or VB.
I'd like to see this work for someone who has an accent... even just to write a letter.
"info make capital" rofl!