An Obvious Question On Rating

This question is probably answered somewhere, but if it was, I could not find it. I’m not one of the testers, but am just asking this in preparation: what is the maximum allowed “rating” for a World? As in E, E10, T, M, AO, etc.
edited by digiexpert on 8/26/2012

[color=#009900]In fact, we’ve finalised and expanded the guidelines - you can now find them linked from the bottom bar of any SN game.[/color]
edited by Alexis Kennedy on 8/27/2012

Thank you both for your answer, my questions on the matter of rating are answered.