Windows Server 2012 R2

Windows Server 2012 R2 is the latest version of Windows Server, currently in the preview stage. It was unveiled on 2013-06-03 at TechEd North America, with a preview release on 2013-06-24. A download version on 2013-06-25 was made available.

This is the Server Counterpart of Windows 8.1. it replaces Windows Server 2012 and was replaced by Windows Server 2016.

Editions
According to Windows Server 2012 R2 datasheet published on 2013-05-31, there will be three editions of this operating system: Essentials, Standard and Datacenter. As with Windows Server 2012, the Datacenter and Standard editions are feature identical, varying only based on licensing (particularly licensing of Hyper-V VMs). The Essentials edition has the same features as the Datacenter and Standard products, with some restrictions.

Changes
As of preview version,

Automated Tiering: Storage Spaces stores most frequently accessed files on fastest physical media

Deduplication for VHD: Reduces the storage space for VHD files with largely similar contents by storing the similar contents only once.

Windows PowerShell v4, which now includes a Desired State Configuration (DSC) feature.

Web Application Reverse Proxy.

Integrated Office365 support.

The return of the Windows Start Button.