Perhaps they could just swap the 2 functions. On the Touchstream keyboard it makes sense though, a single finger types, 2 finger drag of the right hand moves the mouse, 2 finger drag of the left hand moves the text cursor (dragging actuates multiple arrow key presses). 3 finger drag on the right hand marks/drags a window. 3 finger drag of the left hand does shifted arrow-key movement.
4 finger drag of the right hand does scroll. 4 finger drag of the left hand does page up/down, home/end, depending on the direction.
It's amazing to be able to do typing and mousing from the same surface, and cursor control via drags is absolutely wonderful. I even use on shell prompts!
Dragging my left hand up/down goes through my command history, and dragging left/right I can quickly go and edit a parameter in the middle of a long command line!