So yesterday I got my hands on a copy of: Windows Server 2012 Datacenter RTM. So I got home and updated my Network at the house. I logged into my DC (Server 2008 R2) and did a upgrade obviously just as with other versions you need to run the:
Once you run the preps above, you should be good to go with the upgrade of your domain controller.
You can follow the steps below in this: short video: