i had no end of trouble with my wifes itunes when she bought an Imac, she wanted her music off her old computer on to the new one, but as itunes seems to register your device to itunes and all your tracks to one device it won;t let you trnasfer them very easily. (her itunes was bigger than her device, and she only decided she wanted it after i had partially dismantled her old PC so was trying to pull it off the hard drive.
i don't like the layout, i don't like the format, i don;t like the way the software embeds itself so deep in your CPU.
i didn't used to like the fact that it only wrote music in apple format (this has now been changed) which meant you could only play stuff from itunes on apple devices.
Itunes and apple stuff is fine for people who have no interest in computers, but if you want to do anything outside the apple parameters its incredibly frustating stuff ti work with.