Mike Neil is General Manager Virtualization at Microsoft, he posted a blog post after the NY Times article:

Virtualization has long been a core part of server operating systems and this dynamic market is enjoying a fresh round of innovation.  These new technologies will help customers reduce costs, make IT more flexible, and enable vendors to offer more services.   Microsoft believes the best approach for customers lies in establishing a foundation of cooperation between vendors, which is why we strive to regard virtual machines and virtualization technology the same way.  Windows server licensing offers a level playing field to all.  To encourage interoperability, we openly share technology and have published a set of APIs for all our commercially available virtualization products today and provided documentation on APIs for the hypervisor that will be part of the next version of Windows Server, codenamed Longhorn.  We desire open dialog among industry vendors and will talk with any company wishing to discuss licensing for future products. More information on Microsoft’s virtualization strategy can be found on the Windows Server blog at http://blogs.technet.com/windowsserver/archive/2007/02/25/Where-we_2700_re-headed-with-virtualization.aspx