thinning back a few years, the idea that facebook could amass such volumes of personal data based on one's digital activity sparked much the same reaction. in deciding to use their service, there's a clear tradeoff between enjoying the benefits it provides and giving-up (and trusting them with) a lot of personal data - which, naturally, has potential for abuse.
technologies like this new kinect, as well as personal fitness monitors, google glass, smartwatches and other wearable technology, are just a continuation of that trend, now translated more to the physical realm.
it is definitely a leap, as the data being captured is more tangible and the ability to identify one based on it more real, but its still very much the same and feels like a natural evolution as we move more towards a world where everything is connected..
I keep a piece of tape over my camera, but there is nothing physically blocking the microphone.