I would agree, Apple's description:
Slot-loading SuperDrive with double-layer read support (DVD+R DL/DVD±RW/CD-RW): writes DVD-R and DVD+R discs at up to 4x speed, writes DVD-RW and DVD+RW discs at up to 4x speed, reads DVDs at up to 8x speed, writes CD-R discs at up to 24x speed, writes CD-RW discs at up to 10x speed, reads CDs at up to 24x speed
I think their intention is (as misleading as this technical specification description maybe):
SuperDrive read support: 8x DVD+R DL, 8x DVD±RW, 24x CD-RW
SuperDrive write support: 4x DVD±R, 4x DVD±RW, 24x CD-R, 10x CD-RW