The problem with this kind of question is the closed development process of CentOS.
Even Microsoft's development process (public beta, rc, roadmap, release date) is more open than in CentOS.
A good example of a transparent development process is Scientific Linux.
So why is CentOS development so closed? Why users can't have alphas, or betas of this distro and must use some other rebuild as Scientific Linux? If you release this development versions than more people can make tests or can send patches-
Thank's for your answer Filip Bartmann