This should answer all questions: venn diagram

I've been working with Microsoft development platforms for almost 20 years and I've been very resistant to branch into the java community. Switching from C# to Java is only part of the decision. The syntax of these particular language is the trivial part to learn. All of the libraries and frameworks and IDEs and ideosyncrasies that go along with all of them are the bits that I see as the real work. It is hard enough to keep up with any one piece of the Microsoft world (how many *real* WCF experts do you know?) let alone several pieces. I have always weighed all of this when considering taking on a Java (or other) project. So I agree with the plumber/electrician analogy - maybe you don't have zero experience in the new field, but you sure will be junior and while you are getting up to speed, your skills in the other field may fall behind. Maybe I would feel differently if I didn't already have so much investment in the MS world - could I make the switch? Sure...would it be painless? Not at all.