It says under the table "locations based on projections of delayed data" I would guess that they look at where a flight plan is going from and to and interpolate in between.
At the moment it's pretty simple matching based on a few rules, but machine learning is in development. In the case of google, it appears they are using human editors.
This is somewhat similar to a site I have been working on. http://www.newsdive.net I am doing filtering based on story content, but this seems to be based on tags and categories more.