The iPod Touch is usually presented along with the other iPods types in Apple Keynote on September 1. However, as no iPhone 5/4s has been released yet, the release of the iPod Touch might be delayed after the iPhone is out.
The iphone5 will come out when the ipod touch should, i dont think apple will not wont to realese them together or it will saturate the market, so they will realese it before or after the iphone5 is out and as there is no leaks like there is with the iphone5 my guess is it will come out after, if it coms out after you will probably beadle to buy a iphone 4 for the same price as they would bring out a new ipod at.
Plus there is no listing of ios sporting a new ipod as there is with it sporting a new iphone.
This year, iPhone and the iPods may be released simulataneously, there is no reason to stop the annual update of the ipod touches as that will hurt their stock and leave stock holders scratching their head. Its hard to imagine another good time when the ipods will be released besides September. Anyways Apple may be changing Septembers to only release hardware and their WWDC from now on will only release software.