Humanoid robots still have problems staying upright, especially in tricky situations, but it's evident that they're making some progress. IHMC has posted a video showing Boston Dynamics' Atlas robot balancing on one foot on the edge of a plywood board about 0.8 inches thick. The feat is a "lucky run," IHMC admits (it's rare that the robot stays poised for so long), but it's relatively effortless. The worst you see before the fall is shaking as IHMC's algorithm sometimes makes poor estimates of the robot's state.
As brief as the balancing act is, it's telling. After all, many humans wouldn't last that long on their first try... at least, not with the same level of grace. It may just be a matter of refining the technique to get robots that are surefooted in situations that would trip up their organic counterparts.