I just bought an Apple USB Superdrive. I works fine with a macbook air but if I plug it in to a 15" Macbook Pro either a Core 2 Duo or an Early 2008 model it won't work. The optical disc is not admitted when I try to insert it.
If you spend a little time Googling you'll find a 'solution'. The reason isn't as autocratic as you might think - it has to do with the amount of power required to operate the bus powered device. The newer Macs can handle it, the older cannot.