A couple of days ago oneOpenSource published an interview with Linus Torvalds:
In a famous book you defined Linux’s development as an activity “just for fun”. Do you still enjoy it?
Yes. It’s still why I do it. The parts I do that end up being fun have been different over the years - it used to be purely about the coding, these days I don’t write all that much code myself, and now it’s mostly about the organizational side: merging code, communicating with people, pointing people in the right direction, and then the occasional bugfixing myself.