Linux is running behind the scenes. Its running on the data warehouses and webservers. We switched to SUSE Linux from our proprietary flavor of Linux several years ago. I don’t know of any clients that run their desktops on Linux though which is where Linux falls short. Android is of course a Linux based operating system and is dominating both tablets and smart phones.
I think the French police uses all Linux on their desktops now. Or are moving toward that goal.
What do you mean by “falls short”?
Games probably?