This thing is impressive. It's got 4 legs, and can navigate through uneven terrain, mud, snow, and loose rocks. Furthermore, it can handle inclines fairly easily, is able to side-step, and even recovers easily when kicked to the side. Whatever algorithms they're using to dictate its movement seem to have nailed the task. Its movement style is uncannily natural-looking.
I don't know how well it would fit into the role for which it was designed (carrying cargo over land for the military) since in its current incarnation it's rather loud and probably not so durable, but as robot locomotion goes I think that this is a significant breakthrough.
If you want to go straight to the video, you'll find it here.
Now they just need to load some guns on it, along with motion trackers and some collision avoidance, pattern matching, and target tracking capabilities, and you've got a basic robot of doom to unleash upon the unsuspecting populace! ;-)