Indeed, we are using Area 51 to gauge commitment to a particular Q&A site so it does have a certain amount of hoops to jump through. The last time we tried to let people create Stack Exchange sites without demonstrated commitment, most sites did not have enough users to be viable. Area 51 is, so far, doing a great job of identifying the topics for which there is a devoted audience. We also assume that people who are highly committed to Stack Overflow are far more likely to participate in a new Stack Exchange alms therefore we've really built this system for them, the highly engaged, high reputation Stack Overflow user.
What is "highly committed"? - is it scaled by reputation, or is "highly committed" defined at a particular reputation level, question count, or number of answers?
Seems to me that you've been under a rock for the past year or so... if at this point you still don't know what it is... I suggest you look at this page:
Are you not familiar with Stack Overlow? It was apparent to me immediately that they have created a community process to build Stack Overflows for more narrow topics.
> How are they going to make money?
The successful communities will have millions of visitors a month.
