I mean software development in general. About the Advantages: -I see C#/Java copying the functional language features, which isn't supported by default which yields an ugly code, more lines to write. -No one can argue on the amount of the libraries available, but It's more JVM/CLR thing, so you can access it from anywhere -on the concepts not being exotic? well, porting functional language features doesn't really help :) -on the benefit, I believe coding in a functional language is more productive and more expressive, don't you?