Linux (on the desktop) is probably of little or no concern to Microsoft at this point. They've got bigger problems to worry about. If they want to focus on making computers sold with Windows offer the best possible experience it will benefit the most people. Possibly it will make things harder for Linux users but from Microsoft's perspective if the OEM is shipping Windows there's no reason to consider Linux as part of the equation.
My personal opinion is that it is indeed little concern, but a little concern to many parts of MS, which compared to many other companies may well look like a dedicated anti-linux corporation that outnumbers them.
