Here are some important resource links to utilize when digging in to Windows Server 2012 Active Directory.

 

What's New in Active Directory Domain Services (AD DS)

http://technet.microsoft.com/en-us/library/hh831477.aspx

http://technet.microsoft.com/en-us/library/hh831769.aspx

Active Directory Administrative Center Enhancements

http://technet.microsoft.com/en-us/library/jj574139.aspx

Deploy Active Directory Domain Services (AD DS) in Your Enterprise

http://technet.microsoft.com/en-us/library/hh472160.aspx

What's New in Active Directory Certificate Services?

http://technet.microsoft.com/en-us/library/hh831373.aspx