I founfd that the visa information line people were most unhelpful, and had no information! When I emailed them they sent back a reply saying unless you have been asked to contact, you will not hear from us!
So, my experience has been-
August 24-case completed at NVC
October 30- received my interview date for 28th November!
So, hopefully yours will come along soon, but as the ever-so friendly people at the embassy tell you, 'every case is different'!!!
Good luck, I know how horrible it is waiting!