Nothing in particular, other than that it was a fascinating story/pshat, and it also served as a test case for what would happen if the title of a thread is a URL.
What I understood about the walls having ears is that under the right architectural conditions, sound can travel across a diagonal from one corner to another and someone in the opposite corner will be able to hear what should be impossible for him to hear, considering that even people just a few feet away from the speaker can’t hear it.