Linux on the desktop? not happening...
The problem with Linux on the corporate desktop as some stated is indeed not so much an inability for administration, but IMO backwards compatibility.
Setting up and using a Linux environment is indeed rather easy (if you know what you're doing of course). However; the big issue with Linux are the enforced upgrades which you can hardly bypass. That is; if you have a problem with running a version which no longer gets any security updates.
The best options at your disposal here are Ubuntu's LTS (3 year continuous updates) or CentOS. However; even CentOS' 5 support will be discontinued in 2014, see this link:
When you compare that to Windows then it becomes very clear IMO why Windows has the upper hand on the corporate desktop:
Windows XP will stop in 2014 (that is a lifecycle of approx. 13 years (Win XP professional 32bit), Windows 7 will stop in 2020 which would mean a life cycle of 11 years (although one may assume that 2020 won't be the final date).
This is something simply unheard of with Linux environments. And the longer you can continue to use a product the lower the costs you'll need to make in order to test and rollout the new version.
Nothing fanboish here, merely stating facts. Heck; even Linux knows this strategy by heart: "If it isn't broke, don't fix it!".
As for SSH... I think MS' Powershell really takes interesting steps in the right way, even though it still feels quite a bit flakey here and there. I know its not comparable to SSH; its not even an encrypted connection perse. But it does give you quite some interesting commandline based features which doesn't stop at a local machine. Even for remote administration.