Despite Microsoft still keeping quiet on the final pricing of Windows 8, through various small announcements and leaks we're beginning to get an idea of what the price will be. Today, if you head to the Microsoft Licensing Advisor as part of their Volume Licensing scheme, you can actually select Windows 8 Pro as one of the products.
After choosing the Microsoft Open License program for Corporate use, and then selecting a single license-only copy of Windows 8 Pro through the drop-down boxes, it spits back a price of $188. Note that this price is through the Volume Licensing program and will not be the same as the consumer System Builder pricing, expected to start below $100 for non-Pro Windows 8.
Also revealed through the Volume License center is the price for Windows Server 2012 Datacenter ($4,810 per license) and Server 2012 Standard ($833 per license).
Apart from the Volume Licensing and System Builder options, Microsoft is running an upgrade program that will net you an upgrade to Windows 8 for $39.99 until January 31, 2013 provided you're running a previous version of Windows. People who buy a new PC between June 2012 and January 2013 will also be eligible for a cheaper $14.99 upgrade to Windows 8, which some PC manufacturers are refunding.
Source: Microsoft License Advisor | Thanks for the tip Ramesh!