I've worked on some large projects in the past with 500+ database tables but I have yet to see any persistent browser based games or any games get up that kind of table count. I only have 61 tables in Perenthia right now with a few more features to add which could possibly add another 10 tables. I would be curious to see a larger model, to see what kinds of things are handled. Right now I have tables for users, roles, places, things, avatars, skills, attributes, quests, guilds, professions and an assortment of lookup tables for things like item conditions, materials, titles, levels, etc.