I'm using T650 on Ubuntu 13.04 (title) and found next gestures:
This basic functions works by default.
1.Mouse-left: Click touchpad.
2.Mouse-right: Click touchpad from right bottom corner.
3.Mouse-mid: Tap with three fingers.
4.Scroll-vertical: Slide two fingers up or down.
5.Scroll-horizontal: Slide two fingers left or right.
6.Open unity search (same as Super-button): Swipe three fingers up.
Next gestures are not defined by default. You can define them example as 'Keyboard shortcuts'. A custom keyboard shortcut can be almost anything. If you do it this way select the shortcut you want define it will ask for 'new accelerator' and then do the motion.
Gesture - System recognized keyboard button.
7.Three fingers swipe down: Super + D
8.One finger swipe from left edge: Ctrl + Super + Backspace
9.One finger swipe from top edge: Ctrl + Super + TouchpadOff
10.One finger swipe from right edge: Alt + Super + TouchpadOff
Next gestures don't work (as on Windows 8):
Left click as Tap.
Spread or pinch with two fingers (zoom).
Three fingers swipe left or right.
Four fingers swipe up or down.
Four fingers swipe left or right.
I think this is still quite useful touchpad even you can't use all gestures as on Windows 8 where it was designed for. Either configuring those extra gestures I listed isn't too easy.