MS Windows Licensing for 3rd Party Virtualization Platforms

Licensing Microsoft Windows Server 2003 R2 to Run with Virtualization Technologies (VMware ESX Server, VMware VMotion, SWsoft Virtuozzo, and Microsoft System Center Virtualization Machine Manager)
http://download.microsoft.com/download/7/a/a/7aa89a8b-bf4d-446b-a50c-c9b00024df33/Windows_Server_2003_R2.docx

Microsoft Virtualization Solutions:
http://www.microsoft.com/windowsserversystem/virtualization/default.mspx

Licensing Microsoft Server Products with Virtual Machine Technologies (Brief):
http://download.microsoft.com/download/6/8/9/68964284-864d-4a6d-aed9-f2c1f8f23e14/virtualization_brief.doc

Licensing Microsoft Server Products with Virtual Machine Technologies (White Paper):
http://download.microsoft.com/download/6/8/9/68964284-864d-4a6d-aed9-f2c1f8f23e14/virtualization_whitepaper.doc

Multicore and Hyperthreading Processor Licensing:
http://download.microsoft.com/download/f/1/e/f1ecd771-cf97-4d98-9a1b-b86e3f24e08f/multicore_hyperthread_brief.doc

Step-up Licenses:
http://download.microsoft.com/download/a/6/9/a69a4aa0-717a-4f73-bbcd-9d7451fddbbc/stepup_license_v4.doc

Volume Licensing Glossary:
http://www.microsoft.com/licensing/resources/glossary.mspx

Volume Licensing Product Use Rights:
http://www.microsoftvolumelicensing.com/userights/PUR.aspx