In the discussion around Folksonomies and Controlled Vocabularies there’s an implicit assumption that all metadata is created equal. And that one method will “win”. Of course, it will be some organic combination of folksonomies and controlled vocabularies, that will depend on the area of focus.
Geo folksonomies are my area of interest. Though I have pushed the controlled vocabulary of RSS2+Geo, it’s true that a lot of users aren’t going to get into latitude/longitude. They want to talk about places informally, with place names, or use a map.
mappr has built on the flickr folksonomy for effective photo mapping. As opposed to my experiment in leveraging del.icio.us for mapping, mappr uses place names to geolocate. So, without any user’s explicit intention, a large amount of photos are mappable. mappr’s intentions is to “turn the camera-with-GPS problem on it’s head”.
The mappr folks are delving into difficulties and fun of dealing with place names. Just identifying what is a placename ( Nowhere, Utah ), or which place a user refers to ( Paris, Texas ) is very tricky.
One possible process is to collaboratively build a place name database. Starting with the available public data, build a wiki-ish structured hierarchy of places and coordinates. Perhaps something like this already exists? How active is WikiTravel? Wikipedia already lists coordinates for some city entries. It certainly has many public places within cities. Does mediawiki support any sort of structured data tagging? A one time import of public data would be a good start.
But what about precision? For unintentional mapping, folksonomy will suffice. But what about mapping with a purpose? If you’re building a map of graffiti, wouldn’t you want to have precise locations so you can actually go out and see it in person. That level of precision requires more than place name geocoding.
Wouldn’t this be a lot easier if there was a vocabulary? like the proposed mappr tags? mappr may have the groundswell to push a vocabulary .. though I’d suggest using and extending the geo namespace instead of creating an application specific tag. It’s not either/or. Support the folksonomy to get the project and users going, push the vocabulary, especially in tools, for precision.
Users don’t need to be aware of a data structure. RSS, the most successful vocabulary on the scene, is published without any user knowledge. That’s what publishing geolocated weblogs is about. geo.licio.us uses the map itself to determine coordinates. A map zoomable to urban areas, combined with a good geocoder, could make the lat/long tagging process relatively painless. The key is integration with the tools. flickr users are already investing time in annotating their photos; many would be willing to make a couple extra steps.