Well, I'd have to disagree with the automation and networking part. I find that Windows actually is easier to set up networking in.
As for the multiuser system, Windows XP is that, it has multiple profiles and whatnot. Linux has the same (it's more advanced, with the permissions and stuff, but I prefer everyone is root/admin systems anyways).
The things I like about Linux are:
-FREE!
-Open source
-Includes almost everything you need, everything else is free download
-Easy to get up and running, almost all drivers provided automatically
-Really secure and immune to viruses
-Awesome graphics (Compiz Fusion)
-Compatible (with M$ documents, media, networks, and to an extent, programs)