Its got references to all known BTS source materials, as well as materials that are helpful to BTS. Its got lots of NPC's, player characters, pregenerated player characters, equipment, gm and player advice, adventure ideas, house rules, links to helpful sites, and more.
Coincidentally, the site's always open to material by BTS fans being submitted to it (once you've created the new antagonists, monsters and such you were talking about), and the host does commissions for creating characters, adventure fleshing-out, advice, and whatever else you might need to make your game a success.
How do I know all this? Let's just say I'm on good terms with the host of that house.
