You mentioned the ease of restoring a crashed server using Linux. Pretty much the same ease in the windows side as well. Just last week I had the privilege to restore a server due to a botched upgrade with just a few clicks.
This is not my experience. Not unless you have something that takes an image based backup of the server and restores it. I'm talking about a restore where you start with a cd and reinstall the OS and then try to put all of your settings back. With a handful of text files and a few yum commands you are right back in business. Doing Windows is far more of a pain because it's usually installs, next, next, next finish, and then go into some dialog screens, enter some variables, save your config, restart your service, etc.
Linux on a desktop is a geeks version of a toy but that toy is getting better with time. How many years now have Linux fans been saying that this is their year they will take a huge market share in the desktop?
I've been supporting Linux and an RHEL for 10 years...and I've never said it was going to get desktop market share. Like I said before, it's suited for the server room.
With that said, we have thought about moving all of our desktops not in Corp to Linux. Ok, the CIO mentioned it after someone joked about it in a meeting. We quickly changed the topic and didn't allow that person to joke about it again! We have too many people in a whole new world of discovery every time they approach these magical TV sets with the typewriter attached to think about trying to teach them the Linux way
Use the right tool for the right job. We are on Windows desktops, but the overwhelming majority of our web servers and such all run Linux. It saves us a boatload with licensing, and Apache configurations are so simple and straight forward. The OS install is much smaller and much faster. And there is a much smaller attack surface since we run minimal installs with no GUI's, etc.
We still have Windows servers, Active Directory servers, Exchange Servers, Lync servers, Microsoft SQL servers and a little tiny bit of sharepoint. So, we aren't anti-Microsoft, but it's not sure fire choice for a project either.