The Alki Beach example is absolute madness. On one hand, I can't wait until all thousands of my photos get automatic semantic and geographic tagging (I guess that's possible now). On the other, goodbye privacy, we hardly knew ye. It will be interesting to apply this to historical, or just old, photos.
I wonder about info leakage with that one, the poster uses that exact photo as their avatar so if they've mentioned Alki Beach before then reverse image searching might pick it up from context. Ideally you'd want to test it with a photo that's never been posted online.