XWiki is a WikiWiki clone written in Java that supports many popular features of other Wikis like the Wiki syntax, version control, attachments, security, and searching, but also many advanced features like templates, database and dynamic development using scripting languages (Velocity, Groovy, Ruby, Python, PHP, and more), an extension system and skinability, J2EE scalability, an XML/RPC remote API, statistics, RSS feeds, PDF exporting, WYSIWYG editing, an Office viewer and importer, and a lot more.
This is a stabilization release as the end of the 3.x cycle approaches, so its main goal was to improve the Extension Manager and App Within Minutes features. However, this release also comes with a new look and a new default wiki page syntax. Other things to check are the new delete space menu, the space templates, the minimized action menu, the new display macro, and the fact that non-ASCII characters are preserved in attachment file names.
URL: XWiki - Open Source Wiki and Content-Oriented Application Platform (Main.WebHome) - XWiki.org