There is always the tank story/myth http://neil.fraser.name/writing/tank/. Of course, that is more about how a neural network might not be training itself in the way you expect.
This was more a case of the training data not being representative of the actual domain (since Google changed the domain before the presentation). If it were a case of overfitting, the system wouldn't have had the accuracy it had, since it wouldn't work well for data outside the training set.