All existing RPMs of OpenStack that we've found contained problems that prevented components from operating correctly with each other:
1. Incompatible protocol in packaged version of Keystone (already fixed): https://lists.launchpad.net/openstack/msg04876.html
2. Json template bug (already fixed): https://bugs.launchpad.net/keystone/+bug/865448/
3. ISCSI target management troubles: https://bugzilla.redhat.com/show_bug.cgi?id=737046
In addition, there was no packaged nova-vnc in CentOS repositories.
So we've fixed these bugs and established our own repository for OpenStack Diablo. Packages added there have been tested in a real-world deployment.
You can easily install the repository on your CentOS system using wget:
$ sudo wget -O /etc/yum.repos.d/epel-mirantis.repo http://download.mirantis.com/epel-el6-mirantis/epel-mirantis.repo
You can browse the repository here: Mirantis OpenStack Diablo