And is it worth trying to recreate one? I would imagine it's already too saturated. Either way, I was mostly curious about how much these guys actually make (margin-wise). If anyone had some insight on this, I'd love to hear.
It is a serious job that I can tell. Not as easy as creating a wordpress blog. You'll need a solid security guy who fixes bugs for you and keeps stuff updated, an accountant and possibly a lawyer when people start to sue you for not being honest;) Losing money is never easy, some people just won't accept it.
You'll probably need a psychiatrist too to keep your mental health.