XWiki Enterprise, a professional wiki that has powerful extensibility features such as scripting in pages, plugins, and a highly modular architecture, has reached version 5.2 RC1.
The developers of XWiki are getting closer to the final version of this branch, but I suspect there will be several more RS releases before that happens.
According to the changelog, a new "Home" menu has been added when there is more than one wiki, a new step has been added to the Distribution Wizard in order to update the default set of wiki pages, various (X)HTML improvements have been made, and more.
Remember that this is a development version and it should NOT be installed on production machines. It is intended for testing purposes only.