(Another interesting fact: "With combined surface area of 56,512 sq mi, Southern California alone is bigger than England.")
I've been to LA and San Diego traveling as a counselor with teens with disabilities. Spent more time in the San Francisco area. I think if I needed to be around more Buddhists I could go to another country, not sure why my initial reaction was, "I need to move to Southern California." Plus, you can be in a Buddhist country, but the buddhism is cultural, not so much active. I suppose like any religion, you can identify as something, but not so much study or really delve into it. So where is the most Buddhist spiritual intensity? Any why look for it outside, why not cultivate it inside?!
I was disappointed not to see the Triratna Buddhist Community in the entry on Buddhism in America. Also the literal ideas of transmission are rather unprogressive. I guess I hope the new buddhist movements section is expanded. I expect a living encyclopedia to more up to date.