The latest update for Arborwiki is that the database is now hosted on the Localwiki central platform. This gives us updated maps, current software, and additional central hosting support. The cut over was on May 1, 2014.
All of the old Arborwiki URLs still work; you can get to the home page at http://localwiki.net/ann-arbor or at http://arborwiki.org . We fixed a temporary problem where old URLs with a /city/ prefix stopped working.
One of the things that is clear from the effort is that there's a lot of Ypsilanti content originally hosted at YpsiWiki that could, with the right people, be easily hived off into its own project also under the Localwiki umbrella but with its own home page and look.