For those of you running iTunes on a Mac, please take a minute to do this and report your results:
Copy a single song over to your ipod/iphone. Then find a bunch of tunes that will take a while (30 seconds) to transfer to your ipod/iphone. Transfer the tunes to your i-device. While the copy is still happening, delete that single song you previously transferred. Now look: is you big transfer still going, or did it stop in the middle when you deleted the single song?
My experience is that it will stop – i.e. iTunes can’t multitask. Same thing goes if you’re copying some tunes, and then select a new bunch and start it copying – the first batch of tunes will stop copying and the new batch will start, so you may lose some of the first tunes you wanted copied over.
Frustrating.