I'm not a command line geek really, just like to fiddle, and learn to do what I need to as it arises. That doesn't stop me running Mandriva as my main system boot. Secondary boot is Windows, for when I really can't find an alternative application. Third boot option on this machine is now Solaris 10 for x86-64. I've got that far, but I haven't got Solaris under control yet. The SGI runs IRIX, and it would be difficult to make it run Linux due to the way speculative load & store processes happen in the MIPS R10K. There are workarounds, but I have the proper IRIX disks, so part of me says "what's the point?"
Mostly they're just toys. Work PCs are all Windows, and all the TV hardware runs on dedicated platforms under the bonnet (the disk recorders run on *nix (unknown type, custom shell), the Vision Mixer is VXWorks-based with a touchscreen GUI (and very stable). If we go with using EVS systems in the future they run on DOS. No, really.
I tend to find that whichever system I'm using, the only thing that really matters is the interface. If the stuff under the bonnet performs correctly, it's all about the ergonomics of use. The nice thing about Unix/Linux is you can choose what front ends you want to work with.