Where Windows scores highly is in the ability to lock down a machine and impose (and then vary) a central group policy. Linux developers dropped the ball on that one, which is part of the reason why MS has maintained such a stranglehold on the desktop.
I disagree, SELinux has very good policy control, even Solaris had one way back, there are admins out there who are specialists in setting up compliance and security management systems, some of them even know how to do both Windows an *nix
.
I see it all going SaaS because most large organisations now store all their crud in some content management system, e.g Documentum
.