In general, I think the best way to edit a video is to choose a starting point and ending point while playing a video as this is far easier to use than the current editors' paradigm of setting start and end. I think youtube should learn from the cuemongous app on facebook (http://apps.facebook.com/cuemongous) which does a far better job of this and also allows me to use anyone's video to create a remix. Perhaps you guys can implement a UI like that rather than the current "scissors" model.