Within the general concept of Merging Wikis I agree, it would be good in principle to have one uber-wiki that is the central hub of all community things (meta, outreach, strategy...). Each time we create a separate wiki Ward Cunningham kills a kitten.
I wonder - would it be possible in MediaWiki to make it possible for User accounts to be given read/edit permissions to different areas of the Wiki. If that were possible (which I'm sure is a common request from MediaWiki's Corporate users) then we would also be able to merge InternalWiki, CheckuserWiki, ChapComWiki to this uber-wiki. The WMF would also be able to merge their OfficeWiki, BoardWiki, and WikimediaFoundation.org. I'm sure that many Chapters also run at least two Wikis - one for the public and one for their elected Board.
Personally would like to this new uber-wiki be hosted at * http://www.wikimedia.org/* (rather than Meta) which is currently just a placeholder that points to all of the projects. Other relevant additions to MediaWiki would be having universal watchlists and universal User/UserTalk pages as well as the ability (which is coming in LiquidThreads v.3http://www.mediawiki.org/wiki/LiquidThreads_3.0) to Watchlist specific individual threads in talkpages.
On a separate note, have we had a discussion recently about the name "Wikimedia Commons" and whether it would be a good idea to simply call it "WikiCommons" to make it consistent with the rest of the projects? Or, is this a perennial proposal? From what I understand, the reason that it was called that Wikimedia Commons originally was that was created to be a "service project" for the Wikipedia language editions and was not expected to be considered a "sister project" alongside WikiSource, WikiNews, WikiBooks... Now that it definitely IS a sister project, do you think it is a good idea to rename it? I note that a lot of people who reuse our multimedia are attributing it as coming from WikiCommons already anyway (google news search for the termhttp://news.google.com/news/search?aq=f&pz=1&cf=all&ned=us&hl=en&q=WikiCommons&btnmeta_news_search=Search+Newsfor example.)
-Liam
wittylama.com/blog Peace, love & metadata