Slashdot reports that Red Hat has begun testing on Fedora Core 5. From the article:
The next version of Raleigh, North Carolina-based Red Hat's enterprise Linux distribution is not scheduled for release until the second half of 2006 but will include stateless Linux and Xen virtualization functionality and improved management capabilities. Fedora Core 5 Release 1 includes updated support for XenSource Inc's open source server virtualization software, as well as new versions of the Gnome and KDE user interfaces, and the final version of the OpenOffice.org application suite.