I've given up trying to get my touchpad registered correctly. It wants to be an imps/2 device, and I can't spend any more afternoons trying to convince it otherwise (in fairness, it does quite well as an imps/2 device - tap to click, 3-finger tap to middle-click, no horizontal scroll but you can't have it all)
However, I cannot live with the fact that the lightest brush causes the tap to fire.
Is there a command I can use to disable the touchpad when a key has been recently pressed? xinput seems to be my friend here, device appears and can be configured as "ImPS/2 Generic Wheel Mouse"