I just bought my first mac (a macbook) Now I have a 60gb 5g ipod thats half way full of stuff that is NOT on my macbook. However, I want to be able to use my ipod with both my mac and pc. Now I want to transfer my tv shows from my itunes on my pc using my ipod to my mac. When I plug my ipod into the macbook, how do i stop itunes from autmatically updating my ipod with my macbook library (i know on a pc itunes defaults to update automatically). I dont want to erase all of my ipod songs I just want to be able to use my ipod interchangably between my mac and pc.