just a quickie..... i'm about to update the firmware on my Touch from JB 1.1.2 to 2.1 (non JB). I'm on the understanding i must first re-set, via iTunes, my iPod back to factory settings before i download and install the new firmware. Is this correct? this will mean loosing all my music. (re-syncing for me isn't straight forward either). cant i just update/grade over the existing set up so i can keep my music as it is?