It is the same as any Dinki area (dual-income no kids).
In Brighton, the "gay area", known as Kemp Town boarders one of the worse council estates on the South Coast. However, property prices in Kemp Town are about 10-15 percent higher than elsewhere.
You are right house prices in Brighton are going through the roof. Also when we were in Vancouver a very gay city it was an extremely affluent area!! It is definitely the double income no kids syndrome!!!
I think it is essentially a complement to the style and self-respect that (in my experience mainly at work) people who I know are gay possess and maintain, not only in their environment, but in their life in general.