Oh I didn't know that, that is very interesting. I see it now, on the drop down.

How are these territories made? What if someone came along and wanted to make their own 'terrirtory'?

Not sure I agree with you. Someone posting there about an unpopular topic will likely be spending more on fees than receiving because there is no audience for their topic. The same person / posts may be very popular in a niche interest forum. Or perhaps it would even depend on their politics, a socialist poster wouldn't fare well there I imagine (just as an obvious example, but you get the idea). It having no value to the existing audience isn't a great mechanism to encourage wider adoption / diversity of topics and views.

Do we have any idea of the stats on stacker news user numbers/growth?