I think walking in general for exercise is a great way to further wear out your hip and knee joints and cause a lot of excess traffic at your work place. Where I use to work, every break and before lunch ended the group would walk around the grounds. If it was rainning, cold out or excessively hot they took turns walking around in all the offices around the building. Nothing like having 15 people walk by you into the depths of your office to just turn around and come back out and repeat several times.
I do aerobie non impact exercising and unless I do an hour to an hour and half on my cross trainner or recumberbant bike, I do not see any result, other than generating sweat. I think what effects people see are from less stuffing their faces and fluid loss.
