You tell us what you
miss, and we'll tell you how to get it.
I like OSX because it has a bunch of amazing software that just is not available and has no equal on Win or Linux. Apart from that I find it's just a very nice OS to use. Everything works well together, does what I expect it to do within a consistent user/windowing environment, and looks damn pretty while it does. That's why I like it.
I have Vista running on our home desktop PC, XP running on my old netbook PC (now just a media server), and OSX running on my Macbook (which doesn't get much love since the mini 10v arrived). I've used various flavours of linux in the past too. I can see that each has strengths and weaknesses (except perhaps for Vista which is nearly all weakness
). But I choose to work within the OSX environment most of the time for the reasons given previously.