Well the last news we got, they had finished sending out notices to everyone that wasn't in Tokyo. We haven't gotten any news about them finishing up with Tokyo yet, but it's been a little while since that last message so I would assume they're either finished (and haven't announced it), or they're getting close to finishing.
Then before we get anything, they'll probably finish up with the S/mileage auditions since those only have (I think, don't quote me) the finals left, and I'm pretty sure one of the S/mileage girls said something about the new member(s) being introduced at the Summer concerts.
Soo... long post short, we probably have to wait a while longer.