Main candidates are said to include both Motorola and Nokia, but Moto already seems to be doing just fine with the Q, and to be honest, it's hard to imagine Nokia snapping up a company that puts out phones running on Windows Mobile.
Moto includes their Motorola Music Manager software with the player, but we didn't even bother installing it since it's possible to just drag-and-drop files onto the M500 over USB 2.0 (using an interface to copy MP3s and WMAs over from a PC is such a headache).
Dell's team includes the former head of Motorola's phone division (Ron Garriques) and another Moto employee (John Thode) who heads up Dell's netbook group.