I am a network Engineer at my company. The majority of the products we deal with are Linux Redhat and 100% command line of that.
IMO, everyone and their brother has Windows experience, in the computer industy, you need to be able to stand out and I think Linux is the way to go. When I was interviewing for jobs, I tried for a lot of positions dealing with Windows systems, only got one call back. Once I started applying for Linux jobs, I not only got call backs on every job, I also got job offers from every one of them. I am new to the IT field, so my pay is much less than everyone else I work with, but now with even more LInus experience, I can leave here and go elsewhere making much more....but I LOVE my job and would hate to leave it.

Good Luck