I laughed my head off when I read this. This is just another example of how Microsoft is using it's monopoly position to stranglehold the market of operating systems.
I know that Microsoft will never follow through with its threat, and I understand that it would make the market into chaos, but hell: I'd love it if Microsoft followed through with its threat. Then people with computers using Windows might actually REALIZE how monopolistic Microsoft is, and plus, they'd be using an unsupported operating system. Furthermore, the chaos ensuing with people trying to get a supported operating system would make Mac OS X look like a very attractive choice (even if they didn't adopt it immediately because of buying new hardware), seeing as it has most mainstream applications, and for those it doesn't, it could still run them in VPC in the unsupported operating system.