There is very little, everyone just expects everything to work "All the time", no downtime, no hardware failures. And God help us if something does go wrong. Good job I do it because I like it eh?
Oh yes, as for proper operating systems VMS is just brill, one of my servers has been up for 460 days and the last time it was rebooted was when we upgraded the OS.
Thats why we use it in a 24/7 manufacturing environment. As you say, what a shame it is being marginalised.