The mouse preferences capplet is woefully inadequate for modern laptops. Here's a list of what is currently missing, some of which can be found in touchpad preferences (gsynaptics);

 1, Tapping preferences should be included in the mouse settings, enable/disable tapping.
 2, Multitouch gestures are supported by the synaptics driver, for instance I can use two finger and three finger taps for secondary and tertiary clicking. 
 3, Touchpad's can be very different, and require a way to tweak the settings of sensitivity and acceleration in a different way to normal mice. 
 4, Disabling the touchpad while typing is missing from the mouse preferences and touchpad preferences (e.g. executing; syndaemon -d -t -i 2)

I think it's time we started thinking about folding in the features of gsynaptics into control-center's mouse preferences. 

The best way to achieve this is two fold, add a pane to mouse preferences called 'Touchpad' which offers the extra features for instance;
   __________
__/ Touchpad \_____________       

Tapping
 [ ] Enable tapping
     [ ] Disable tapping while typing
 [ ] Enable two finger tap as secondary click
 [ ] Enable three finger tap as tertiary click

Scrolling
 [ ] Enable vertical scrolling
 [ ] Enable horizontal scrolling
 ( ) Use edge scrolling
 ( ) Use two finger scrolling
___________________________

The second change should be to the general/motion preferences and is slightly different in that it should detect that the user is using a touchpad, and work to provide a set of motion preferences which compliment the touchpad, when a mouse is being used the preferences would favour the mouse also, providing comparable motion on both devices.