Update: Since some of you have asked, we'll try to explain a little like what walking with the legs (the ones in the above picture at least) was like. Firstly, the leg motors run on a kind of timer, once you start moving, the computer on-board gets a "sense" of how quickly you'll be walking and begins to push and pull the motor to that rhythm. As you speed up or slow down, you can feel that "timer" catching up. The general feeling wasn't that it was adding that much to our movement -- it's obviously intended for those with some issues already, not people who are necessarily walking normally. Still, you could definitely feel the "legs" exerting a kind of tension on your muscles as you moved back and forth, and the feeling of having more power in your gait was absolutely present. Kevin's description of the second unit was that it was more difficult to walk (and there was no push / pull of a timer), but that he could sense the unit supporting his weight -- though it wasn't as if he could simply put all of his weight on the device. That unit certainly seemed to have a more substantial impact for those without a medical issue or related impediment. If you've got more specific questions, feel free to let us know in comments and we'll try to answer them!
Engadget goes legs-on with Honda's walking-assist devices