The first Release Candidate of the upcoming FreeBSD operating system has been announced and it is now available for download and testing.The developers of FreeBSD stated in the release announcement that there would be another Release Candidate version besides this one, which in turn would be followed by the final release.
The doc and ports repositories have been moved to SVD and the developers have decided to not export the 9.1 release branch activity to CVS. Therefore, csup/cvsup update mechanisms are not available for updating to 9.1 RC1.
Users of earlier FreeBSD releases (FreeBSD 7.X, 8.X) can use freebsd-update to upgrade to FreeBSD 9.1 RC1, but they will be prompted to rebuild all third-party applications.
Download FreeBSD 9.1 RC1 right now from Softpedia. Remember that this is a development release and it should NOT be installed on production machines. It is intended to be used for testing purposes only.