Personally, I don't know whay people keep publishing this sort of junk. Linux is no better or worse than Windows. Even an old NT4 box can be put on the Internet, have high uptime without needing reboots all the time. When you look at many server offerings they make a big deal over the fact that they have reboot switches regardless of the OS being used. This suggests to me that there's a huge number of sysadmins that can't keep a box up and running regardless of OS.
Windows and Linux / *BSD / Unix etc... are different OS's and will of course have different costings associated with them. Any OS will only be as secure as the sysadmin, a fully trained & experienced system admin will have a better system reagrdless of OS. I came across an NT4 box on a secure LAN the other year that had been up for over 500 days (it was 540ish) and was only taken down to install a new tape drive, if that's not stable, then what is? I have a Linux box on a customer site that's been running without fail or reboot since I installed it last summer (until today when a powercut lasted longer than the UPS

).
Being experienced in both *nix and Windows OS's my servers enjoy stability and good uptime whatever OS they are running.
Each OS has it's own strengths and weakness and those who must only run their chosen OS because it's better then OS xyz... rather than because it's the best fit for the customer's needs are far too shortsighted to be left in charge of a system
I've seen people try to run Linux in an environment where they are the only team member with Linux skills, all the rest were MCSE (or multiple MCP's). On this occasion I rejected the request to install the Linux box on the network on future supportability costs. The training costs to put this single Linux box on the network far outweighed cost savings on a Windows server license (even at full retail cost). There was nothing in the application that required a Linux platform other than 1 person's desire to get Linux on their CV.