Of corse Apple will come out with the next itouch. If they don't, they will have a bunch of angry people with pitchforks and torches at their doorstep within days of Sept. 12.
I'm not sure if they're going to come out with an iPad-mini though. It would either be a pain for developers to come out with apps for 3 different screen sizes instead of just 2, or it would be a very toned down version in order to get it into a decent price range (think of a netbook compared to a laptop). Then again, Apple has done some pretty amazing things before, who knows what they might be able to accomplish with the iPad-mini?
Another thing apple might do is start calling the itouch the iPad mini, again, who knows what apples doing.