Patently Apple today shows off images from some recently filed Apple patents that seem to detail additional multi-touch language. These gestures could easily find their way into upcoming Apple software updates/products (although probably just a few at a time). We supposed we should get around to learning this stuff at some point.
Also, another interesting but unrelated feature in the Patently Apple post: iPod adjusts music tempo based on your performance. For example, if your heart rate falls below target, the tempo of your music increases to help get you back up to where you want to be. And vice versa. Smart.