I recently got to interview Peter Curry, one of the makers of Mini Metro, for Digitally Downloaded. You can read the interview here.
I would like to use this opportunity to mention I consider Mini Metro one of the more brilliant game designs ever (and also one of my favourite game ever, but that is not the point). True, it is an exercise in minimalism; but there is more to it. I used to program simulations for complicated computer networks and factory floors myself; however, the thought of turning those into a game never occurred to me. I guess that is the difference between genius and average.