Apple's most recent patent is for a "multi-touch gesture dictionary".
I'm most interested in figure 2, which suggests using a thumb and
finger pinch to cut content, and spread to paste (functions not
currently available on the iPhone). The patent describes thumb and 2
finger and 3 finger actions, as well as clockwise and counter
clockwise gestures. Some of them seem quite intricate, but the simple
ones could be fairly intuitive.