A friend's got a Mac Quicksilver that came with a DVD burner.
I went to go buy some blank DVD discs but was asked what kind I needed (huh?). The person told me that there are "+" type and "-" type of blanks and the one that I needed would be determined by the burner.
Be sure to read the information on Apple's homepage (www.apple.com) about firmware updates for the Mac DVD drives, also called Superdrives.
Also be sure to install the correct firmware update!
I haven't had personal experience with the firmware updates, so continue AT YOUR OWN RISK. My iMac 17" is brand new and doesn't apparently require a firmware update. (Am I wrong?)