I've never understood the fascination with voice control. It's clumsy, it's inaccurate, and honestly it's a bit embarrassing to use alone or in public. Yet, "everyone" seems to want it, despite the fact that spatial-sensor-based (e.g. motion sensors, Kinect, etc. -- note that I'm not talking about gestures, which have the same problems with ambiguity as voice) and tactile controls are much more efficient.
Reading this made me picture trying to drive a car by voice: "Turn left. Left. Further left. More! AHH! NOT SO MUCH!" Here voice control seems like a desire to avoid having to clearly specify your request. "Didn't the car KNOW where I wanted to go? Doesn't this spreadsheet KNOW what numbers I want? Doesn't this fast food menu KNOW what food I want? Maybe if I could just tell it..." I suspect that voice recognition will be popular in the future, but it will seem a lot less sexy if users are still required to clearly specify what they want.
You've got it exactly -- the more important thing, IMO, is systems "knowing" what you want, predicting your behavior, in a way that is completely effortless, transparent, and expected. I'm doing that now with my startup, using pre-scripted actions, but hope to see user-adaptive, learning systems (e.g. the Nest thermostat) find their way into everything.
