This release comes with multiwiki support enabled by default: users are able to create new wikis without the need to install additional extensions. This is possible because the Workspace Application has been integrated in XWiki Enterprise. We stopped the support for XWiki Enterprise Manager as a consequence. Apart from this, the new release brings a Solr-based live search (to replace the one based on Lucene) and the ability to track active XWiki installs. The Distribution Wizard has a new step to upgrade all wikis. Developers will be interested by the new Wiki Stream framework which can already be used to export large wikis in XAR format. A lot of bug fixes (135) and many improvements (50) complete this release and make it worth trying.
Full release notes available at http://www.xwiki.org/xwiki/bin/view/ReleaseNotes/ReleaseNotesXWiki52
See http://jira.xwiki.org/secure/IssueNavigator.jspa?reset=true&jqlQuery=category+in+%28%22Top+Level+Projects%22%29+and+fixVersion+in+%28%22%35.%32%22%29+and+resolution+in+%28%22Fixed%22%29 for more details