Complex sentence: Additional improvements were made in Windows Server 2003 R2, Windows Server 2008 and Windows Server 2008 R2, and with the release of the latter the domain controller role was renamed "Active Directory Domain Services".
Split into simpler sentences: Additional improvements were made in Windows Server 2003 R2, Windows Server 2008, and Windows Server 2008 R2. With the release of the latter the domain controller role was renamed "Active Directory Domain Services".