Suggestion: We could easily import the existing lists into my implementation.
Magnus
Only the major ones please. Many of the lists in WikiEn are really obscure and special purpose.
IMO there should be very few categories (at least at first); One for each major category that is already on, for example, the en.wiki's main page (science, mathematics, physics, Linguistics, etc - the whole lot) along with type categories like "biography", "city/town/village", "country/nation", "subnational entitiy", "stub" etc.
Keep it simple please (at least at first). If /that/ works then we can slowly expand the system in a measured and thoughtful way - voting for new categories may be a good solution here in order to prevent a rapid expansion of categories that would render the whole system useless.
I'm very weary of allowing just anybody to create any category since from a database management perspective it would be easy for people to create many different variants for the same intended category ([[category:biology]], [[category:life sciences]], [[category:life science]], [[category:living things]], [[category:the study of living things]] etc). And having too many categories will be very difficult for people to remember and very unwieldy for people to choose from in a category search. Let the lists stay for the obscure stuff.
We also need to devise guidelines for when to assign labels. Again from a database design perspective: If this is not done consistently then the output or any sort will be suspect and perhaps complete garbage. As KQ pointed out we could assign the category 'crime' to [[Jesus Christ]] along with the category of 'biography' so that JC shows up in a list of criminals. But is JC most famous for being a crime figure? No! He is famous for being a religious figure so the category 'religion' would be there but not 'crime.' Same for [[Bill Clinton]] ([[category:biography]] and [[category:politics]] apply there).
With categories in place then one day we could have our special pages use these tags for things like Recent Changes. RC in the English Wikipedia often has 10 or more edits a minute now! It would be nice to have the option to only see articles that may interest the user (well for me that would be everything but one of my biology professors may want a recent changes that only displays articles relating to mathematics, the sciences and economics).
This will become absolutely necessary if we continue our quasi-exponential growth pattern for WikiEn; one day in not too many years (fewer than most people probably think) there will be an average of hundreds of edits a minute! We need to sort that out somehow or no human will bother looking at RC anymore and will only revert vandalism to articles on their watchlists (even with sorting, bots would probably have to help with automatic 'probable vandalism/copyvio detection' - outputting results on a separate RC for that type of stuff - maybe even by assigning those categories to articles...).
Alas it looks like Wikipedia is growing up. This time next year WikiEn Wikipedians may start to specialize their edits based on which categories they choose RC to output and several other language Wikis may follow the year after. Our small town is beginning to show signs of emerging cityhood (or has WikiEn at least already become a small city?).
We are going where no wiki has gone before. There is both danger and opportunity in that.
-- Daniel Mayer (aka mav)