Re: @ Adam payne
One issue that I heard about was that the device(s) have a far longer life than the OS on the underlying support terminal. So your MRI/CT whatever scanner might have been built before a newly discovered problem with a 5/10 or more year old device becomes apparent.
I fail to see exactly *WHAT* there is to any of these control systems (medical, industrial, etc) that is SO operating-system dependent. Seems like if something is so dependent on a particular brand/revision of an OS, it was shitty design/coding in the first place. And I can only see *that* element getting worse.