And also, the observation made in the OP: you only get one chance at a big-bang introduction, so it has to be right. (Obviously Segway failed on this point.)

And also, the observation made in the OP: you only get one chance at a big-bang introduction, so it has to be right. (Obviously Segway failed on this point.) With Glass, they have decided to do it incrementally, rather than Big Bang style.