Just saw over at the MTR forum where some external optical drives, OWC Mercury in particular, are no longer supported in Snow Leopard. It seems in an effort to slim down the system Apple has not included drivers for some peripherals and printers.
The poster said;
I spoke with Apple and they said they did a lot to slim down 10.6 which included removing some of the plug and play support (drivers and printers etc). It may be up to developers to include such drivers with their programs.
#441583 - 08/26/0912:01 PMRe: Snow Leopard dropping some plug and play items.
[Re: Jim_]
MacBozo
Nut Dood
Registered: 04/20/02
Posts: 16605
Loc: Pinellas Park, Florida
It wasn't OS X that seemed to have changed my Que CD burner, but Toast 9. In T9, I can only read from it - can't write to it. Haven't tried writing to it at the OS level, though.
Snow Leopard makes sure you always have the most up-to-date driver so you can get the most from your printer. When you plug in a printer, Mac OS X can download the latest driver available over the Internet. And it periodically checks to make sure it has the latest driver. If not, it downloads the newest version through Software Update. Easy.