Why is it that we never get a simple answer to a simple question?
Don't say 'we' like you speak for more than yourself, anonymously at that. It has been answered...The CVS, bug tracker and the devinfo list are public information. That's where development happens. Shad builds the iso's and runs the servers. There was discussion recently on the devinfo list about what bugs are blocking RC1. I don't think there are too many, check yourself in the bug tracker, sort by milestone. I think you could say RC1 could be the 8.0 release, unless there is something major that comes up in testing shortly after.
I think you missed something basic. If you log in as root, mysql does not require a password. And there is a contrib for phpmyadmin, because not everyone wants or needs it. Google 'phpmyadmin exploit' for a few reasons why.
Also, there are 1000's using SME8 beta. I believe 8b7 was just built to test a change in the installer, but you are right it was not released. A further beta or release candidate has not been built as far as I know, but most of the rpms that go into it may already be available in updates and updates-testing. The milestone in the bug tracker is used as a target as when that bug should be fixed, ie, they should be fixed in RC1, not that there is an RC1 release.
So, who makes the decisions? You do. Use SME 7 or SME 8 beta, or use neither.