Ok, I just drag and dropped some MP3 files (tagged with MediaMonkey) onto my partner's S639 and my S739 (in its default MTP mode). The only tag that didn't transfer properly was the year field, but everything else is in order including the title and even the album art. When I drag and dropped the same files via UMS mode, all tags appeared correctly including the year field and album art. Hope this helps.
5/31/09 at 6:46pm