Their betas are open, but you may not receive much in the way of updates (including security updates) if my experience with the RHEL 6 beta was anything to go b

Their betas are open, but you may not receive much in the way of updates (including security updates) if my experience with the RHEL 6 beta was anything to go by. You should be able to flip into CentOS 7 fairly easily when they release, though.