Files required to perform the update should be on the servers within a few days.
Then you can update from server manager or using YUM from the command line.
From the Development mailing list:
"The development team is very pleased to announce that SME Server 7.0rc1 is on its way to the mirrors.
We would like to thank everyone who has helped with the development and
testing of this release.
Thanks,
Gordon
SME Server 7.0rc1
=================
****************************************************************
* IMPORTANT: Pre-upgrade step for 7.0pre1 and 7.0beta releases *
****************************************************************
Before upgrading to 7.0 from 7.0pre1 or any of the 7.0beta
releases, you must run the following command:
kudzu -q
If you do not do this _prior_ to the upgrade, your system may
not boot. If this happens, please see the workaround here:
http://bugs.contribs.org/show_bug.cgi?id=698***************************************************************"
Dave