Its finally here, the most requested feature for YouTube5: keyboard controls. Its taken me a long time to get around to implementing these correctly, but its done now.
The available controls are:
Left arrow: Back 5 seconds
Right arrow: Forward 5 seconds
Also included in this update is a rewrite of the fullscreen interface. YouTube5 no longer uses the Apple provided full screen controls, which allows it to look much nicer and function more reliably. And yes, keyboard controls work in fullscreen mode too. Enjoy the update!