Pretty low. It's an Apple tradition to refresh iPods in September, and there would be no point launching the new product before the promotion ends... unless they run out of old iPod models.
And even if a new iPod Touch did come out, it would be excluded from the back to school deal. As the previous poster said, it's to clear stock ahead of refresh.
If you want an iPod touch and a Mac, just shop around a bit. B&H Photo Video (http://www.bhphotovideo.com) has low prices on both. What were you looking to buy OP?