I'm looking for some insight as to what to focus my studies on and what to master; Linux, Unix, Mac, Windows, Cisco, among the many other things. I'm only 23 so relatively young into this field and extremely curious about the pros' insights. So far, my current job as a Network Engineer deals with a Windows environment (Server 03/08) so I have some experience with that.
Thank you for your time as I know it's a rather broad question, sorry. =/