I'm curious how things like "bootylicious" in San Francisco and what appear to be mostly personal photos like "griffith observatory" in Los Angeles, and perhaps

I'm curious how things like "bootylicious" in San Francisco and what appear to be mostly personal photos like "griffith observatory" in Los Angeles, and perhaps artistic things like "lighting shadow" in San Francisco made the cut. Is it that at least two different accounts posted photos with those tags in the same general vicinity within a certain time elapsed? Maybe it would help filter out less relevant results if events without any photos featuring large groups or crowds of people are removed, since those typically go hand-in-hand with notable events. If there could be a way to separate out sporting and music events, that would be nice as well. Prime featured content would be large groups of people in the streets, with bonus points if there are things on fire. Another would be natural disasters (floods, tornadoes, hurricanes, earthquakes, tsunamis), which most likely do not contain pictures of crowds in the streets, but probably do contain damaged or flooded buildings. Another might be a disease outbreak, perhaps with pictures of individuals with lesions or other visible symptoms, maybe in a medical setting. War zone events like the shelling of a neighborhood somewhere would be interesting, and might fall under the damaged building filter for natural disasters. Maybe pictures of tanks or other heavy military equipment rolling into a town, or helicopters flying overhead. UFO sightings. Pictures of crashes and accidents are always popular as well, and might only have a few emergency personnel around. Political events would probably fall under the large crowd filter. What else?