MediaWiki is a Wiki software package licensed under the GNU General Public License. It is written in PHP and uses an underlying MySQL relational database. Its logo symbolizes how its markup language uses brackets [[picture of flower]] to link articles together, in contrast to CamelCase.
Mediawiki is being developed by the Wikimedia Foundation. Lead developer is Brion Vibber.
from wikipedia
Related: Wikimedia, HowTo/BecomeAMediawikiHacker
We just upgraded to Mediawiki 1.4.
Current Versions
The current version of Mediawiki.org itself is 1.6alpha [1]
The current release candidate version of MediaWiki is 1.5rc4 (released on 2005-08-29)
The current stable version of MediaWiki is 1.5.0 (released on 2005-10-05)
The current legacy version of MediaWiki is 1.3.15 (released on 2005-08-29)
New features in 1.4
* 'Recentchanges Patrol' to mark new edits that haven't yet been viewed. * New, searchable deletion/upload/protection logs * Image gallery generation (Special:Newimages and <gallery> tag) * SVG rasterization support (requires external support tools) * Users can select from the available localizations to override the default user interface language. * Traditional/Simplified Chinese conversion support * rel="nofollow" support to combat linkspam
New features in 1.5
MediaWiki 1.5 continues the architectural changes started in version 1.4. Its most notable change is a substantially redesigned database schema, which finally completely decouples text storage from article revision tracking. This is expected to increase the speed of various operations like page moves and generating page history listings, as well as allowing unchanging bulk data to be stored outside the database.
New features in 1.6
Major plans for 1.6
* Case-insensitive, case-preserving page titles * Localized sort order for sorted lists * WYSIWYG based on FCKeditor