Microsoft quietly published new pricing and licensing sheets for its coming Windows Server 2012 R2 product.

The bad news: Those who want the Datacenter version are going to have to shell out 28 percent more for the R2 version than the current Windows Server 2012 Datacenter release. The Windows Server 2012 Datacenter SKU costs $4,809 (plus additional client-access licenses, priced separately). The Windows Server 2012 R2 Datacenter SKU costs $6,155, plus client-access license fees. (These are prices for the Open NL version, which is the highest priced volume-license version.)

Pricing for the other three Windows Server 2012 R2 SKUs remain the same as they are for Windows Server 2012.

Here are the new prices for the four Server 2012 R2 SKUs (Datacenter, Standard, Essentials, Foundation):

Users who are Microsoft Software Assurance (SA) licensees and who already have Windows Server 2012 won't pay anything additional to move to the R2 version of the product, according to the datasheet. Windows Server 2012 users (whether or not they have Software Assurance) don't need to upgrade their CALs; they can use the same CALs on both Server 2012 and Server 2012 R2.

"Anyone who did not purchase Software Assurance on their previous server licensing (Windows Server) will need to purchase their server licenses all over again if they want to upgrade," said Aidan Finn, a Microsoft Valuable Professional (MVP) with an expertise in Virtual Machine who works for MicroWarehouse Ltd, an Irish Value Added Distributor, as a Technical Sales Lead. That's why business users may want to consider purchasing SA if you are virtualizing Windows Server, no matter which hypervisor you run because of the host/VM licensing system for Windows Server, Finn added.

The Datacenter edition does offer users unlimited installations of Windows Server on licensed hosts, which can be cheaper than licensing lots of VMs via the Windows Server 2012 and R2 Standard editions.

In fact, that's what Microsoft officials are saying when asked about the reason for the price increase in the Datacenter edition with R2. I asked a spokesperson what is behind the 28 percent price hike and got this statement:

"Microsoft is making these changes based on market conditions and based on the overall increased product value and choice. For example, with Windows Server Standard Edition and Datacenter Edition customers can determine the option that works best for them, based on their virtualization needs. The Datacenter Edition licensing is optimized for highly virtualized environments, with unlimited virtualization rights and the flexibility to add or move virtual machines across licensed servers without tracking the VM count on a server. And, the Standard Edition is ideal for servers that won’t be highly virtualized, providing two instances per license. Customers can also choose to assign multiple Standard Editions licenses to a single server, in order to increase VM density on that server."

Finn noted that enterprises who are willing to license all of their Windows Servers under SCE (Server & Cloud Enrollment) get access to "an easy-to-budget-for bundle covering the private (Windows Server, System Center, and more) and public cloud (Azure only)."

"Businesses that are interested in the Essentials edition will be glad to see that they can virtualize it under the new version of the license," Finn added.

The four Windows Server 2012 SKUs are Foundation (available to OEMs only); Essentials; Standard and Datacenter. The Essentials SKU is for small/mid-size businesses and is limited to 25 users. The Standard and Datacenter SKUs round out the line-up.