if she sims 3 comes out at the very start of june, they have to roll it out at least a good week or two before that. if there is a bug that stops the sims from running, EA will not be happy 😛.
i can't see them rolling it out with snow leopard.
i am betting middle of may for .6
5th of june it says the sims is out, so it has to be in may. really anyway. if not apple must be getting confident.