I use mine as a CD player, via it's FireWire output into the FireWire input of my Apogee Dac.
Macbook Pro As CD Source
I recently purchased the latest Macbook Pro. I kind of like using it to play CDs sometimes when listening to my stereo setup. (Macbook Pro to W4S DAC 2 to Bryston 14BSST) Sounds pretty good even being fairly new. Does the Macbook as a cd source have potential, or is the best it can perform going to be limited to a subtractive sound?