if your ipod is formatted for PC (fat32), then it'll be backwards compatable with mac - if your ipod has been used on a PC, when you load your library onto your mac, and update your ipod with the music from the mac, your ipod will actually still say 'Windows' under Settings>About>Format.
but they need to be formatted for windows (to fat32) cause windows doesn't support the mac format.
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'yeah line stuff blows, i got a pair of the new pollards and once i took the wrapper off they spontaneously combusted' - schlonginator