Informant38

If you bump into people (we tried it many times) it was no worse than bumping into people as a person. Actually it was better, because the bumping causes the handlebar to move back and that does a braking action, unlike a person who would just continue forward with their momentum. The wide tires distribute weight, so running over a toe isn't too bad. (It doesn't mess up grass much on a golf course, either, I hear.) The units we used raise you off the ground, so tall people have to be careful about bumping their heads on branches and things that they didn't previously need to watch out for. Like someone running through a crowd pushing people with their elbows, an impolite person can be impolite on a Segway, too. Social norms will probably develop for different locales. The fact that you don't have to keep moving to keep from falling off (as you would with a bike or scooter) will lessen the tendency to push the limits of decency when encountering people in your path.
What situations can you use it in? Won't snow and rain mess it up? What about sidewalk curbs?
Gary told us in his talk a bit about the testing being done by the U.S. military's Special Operations people. They have souped up units, going very fast, carrying lots of weight, and push them to their limits. (I'd assume that Special Ops people don't get nice sidewalks to ride on.) He wasn't allowed to show us pictures, but imagine this.......

dan bricklin on Segway