I wrote that one. It has nothing really to do with the religious factions found in Blood and Relics.
I was simply playing with Chucks rules for secret society creation and applying it to the various dragons found in traditional D&D. So I wrote a secret history for dragons and then outline cults for both the colored and metallic dragons.
All in all, the issue contains a secret history, 2 base secret societies, 1 prestige class, and 2 new rituals.