I just synced my 2.2.1 3g with my pc, having the latest version of itunes, and when I played back the music on my iphone, it was all messed up.
Whole lumps of music from the end of the song are put at the beginning and the other way around. The music I was syncing was on a usb hdd drive, I added it to my itunes library, and synced it with my iphone attached to the laptop.
I had no music before on my iphone.
The data cable is a bit used, I can see some wires at an end of it, but everything went ok, it synced 298 songs without any problem, without saying that the sync was cancelled or anything.....