Some time ago it was proposed to develop trees from the Wikipedia Main Page, so that one could identify categories based on their propinquity to main page topics. So for instance, [[highway]] which is linked from [[transport]] would be classified as [[category:transport]] (pages could of course have multiple categories, with degrees of separation from the various main page articles noted, some cut off (number of degrees away > 5 perhaps, would be used). (e.g. [[category:blah, degrees:2]]
This function would be automated (or semi-automated), which some may say is not sufficiently wiki; on the other hand, it would allow us to come up with a first cut classification for 130000 articles, which will take a bit of time by hand.
I believe this was done for [[philosophy]]. See [[List of philosophical topics]]
What is the status of [[Wikipedia:Category experiment]]
David Levinson