Do I need to know Linux to administer CiviCRM? This is not a rhetorical question :) . And it's a question I wish I had asked three and a half years ago.
My answer now, to my self of three and half a years ago, would be: No, knowing Linux is not strictly necessary, especially if you use a hosted version of CiviCRM, like Powerbase or CiviDesk, or have a partner like Fuzion or CiviCoop doing your Linux server set up and maintenance; but Yes, knowing how to use a flavor of Linux would be really helpful, regardless, especially if you want to understand what's going on "under the hood" with your Linux server, if that's what your CiviCRM installation is hosted on.
I believe there are three good answers to this question - Yes, No and Maybe.
Your thoughts appreciated....