"The CentOS Project is happy to be included as a supported OS by Microsoft in their Hyper-V system, but I do not agree with the statement by The Register that CentOS is now a 'First Class Citizen.' We have been a 'First Class Citizen' in the Linux world for quite a while. CentOS is currently the most used Linux distribution on the top 1 million Web servers on the Internet...
"Our webserver usage is more than Red Hat Enterprise Linux and Fedora combined as measured by W3Techs.
"I am sure the reason that Microsoft picked CentOS to support is that they were looking for an Enterprise level product that was available with no added cost for their customers. CentOS meets that requirement. Here is a blog where they explain why they picked CentOS (it was
because of our market share and at the request of their customers, not to 'get back at' anyone else).
"With respect to Microsoft, as long as they abide by the OSI licensing requirements for any software they distribute, the CentOS Project is fine with them distributing and supporting CentOS for their customers."
So Hughes believes the advantages of his distro and its free-from-cost status are the big reasons why Microsoft chose to support CentOS on Hyper-V. While you can't take that away from him, I can also see Microsoft playing both ends against Red hat in the middle: get a free enterprise distro, and put the screws to Red Hat at the some time.
All of this Hyper-V/CentOS drama underlines my original point: Red Hat must keep a strong stake in the virtualization platform, if only to avoid dramas like this, where a vendor that doesn't like Red Hat (and there are so many) opts to support Red hat's competitors.
Better for Red Hat, then, to keep pushing KVM as far as they can so they will always have a safe haven in virtual space.