Samsung posted today the full specs for SW-240B. It supports 40x writing, 12x re-write, 40x reading and 8MB buffer... Key feature

Writing(CD-R) 40X, Rewriting(CD-RW) 12X, Reading(CD) 40X,
High Capacity Buffer Memory(8MB)
Reduces noise and vibration with DVA(Dynamic Vibration Absorber)
Supports variable packet CD-R, variable and fixed packet CD-RW read and write
Supports Mt. Rainier

Data Transfer Rate Record: 40X (6,000 KB/sec)
Rewrite: 12X (1,800 KB/sec)
Read: 40X (6,000KB/sec)

Burst Transfer Rate
PIO Mode 4 (16.6 MB/sec)
DMA Mode 2 (16.6 MB/sec)

Recording Capacity
CD-RW Disc 700/650MB (type 80/74)
CD-R disc 800/700/650/550MB (Type 90/80/74/63)
Interface EIDE/ATAPI
Buffer Memory 8MB
Flash Memory 512KB
Drive Mounting Horizontal/Vertical
Average Access Time 100ms
Supported Disc CD-R,CD-RW,CD-DA, CD-ROM/XA,CD-ROM Video-CD, CD-I, Photo CD,CD-Extra,CD-TEXT
Audio S/N Ratio >75dB
Channel Separation >65dB

Writing Method
DAO(Disc At Once), TAO(Track At Once), SAO(Session At Once), Multisession, Packet Writing (Variable, Fixed Packet)