I'm interested in helping out in the development of mediawiki. I think it's very good, but one that seems missing is a good system for metadata and cross indexing information.
That might not be the best way to put it. As I see it, an article would include more than just the text of the article. It would have a summary (possible present on the page), and also metadata (like the classification for an organism). e.g., on an article for a family of turtles, say Chelydridae, you might want to list all of the genuses. Instead of searching and hoping you have them all, then copy/pasting or making your own summaries, you could just do something like
[[wikipedia searchForArticlesWithTags:genus,family=Testudinidae] listData:scientificname,commonname,conservationstatus]
This would then automatically get all of those genuses, with the information specified, and would update if anything changed or new ones were added. You could also automatically grab summaries, which are quite common [someArticle getSummary].
Something like this could also keep data in sync. I've seen several instances of conflicting information between an article, and a small summary in another article.
Is there something like this in progress? I'd like to help, but I'd like to avoid duplicating effort on something someone is already working on. I know how to program, and know a small amount of PHP.