The license transfer is online as well.
You go to My Support and then click on "ask a question".
Under Category you click on the first selection which is "Activation". When you do that another box will pop up and you select "License Transfers". I have used it three times and it has worked every time.
My experience has been that the transferred license can be upgraded. That might be related to special promotions offered by Sony but the license I transferred (Vegas 5) was upgraded to Vegas 8. I have only ever purchased one full version and that was Vegas 4.