I'm looking at making a career change from "IT generalist" to a more specialized field.
I've been employed as a systems administrator for the better part of 10 years, and have general skill in Linux, virtualization, scripting and hardware.
My consideration is also bound to time, eg. Java / C# is in high demand, but I understand that learning Java will take several years and as I'm not in a development environment I won't get the necessary experience, therefore it might be unrealistic to try and learn Java / C# and trying to get other/better work.
I want to make the move within the next 2 years.
So my question: Which field would you specialize in if given a 1 - 2 year window (with the aim of making a career move)?