Well, I really hope that more worlds will be created, anyway if that would happen it probably won't until she finished with Millenium's Rule (probably 3-5 years) and if that happened we could just take the forum out.
Also If Kyralia series and Age of the Five Series end in Series, shouldn't Millenium's Rule end in Series too? Also, should we should change Age of the Five Series into Age of the Five Trilogy? As Trudi is not planning to write more books on that world. I don't know if you got my point.