When creating a world in superflat with structures on, I encountered a village. Something was off, however. There were no stairs. Upon further inspection, there WERE stairs, but they did not load properly, just a corrupt block of space where one could not pass through in it's place. If one were to place a block in the stair place, the block would become the stair, and would seem like you lost the block to nothing. However, you never lost the block and could still place it in a different place. It was easy to see where the stairs were, as the common minecraft lighting bug was in it's place.

Another bug worth noting is that the top half of doors will not load (also shown in screen shot).