Like Mac OS X says they don't need any external components to burn labels - that's the reason why they're hyped about, you just flip the disk over, pop it back in and burn the label.
I own one, and I have to say they're overrated. Not only does it take between 20 and 40 mins to burn a label, in my opinion there's very little contrast in the resulting images - it seems to me to be very faded, now I'm not sure whether that's a problem with the media that came with the drive or not, but it certainly doesn't seem worth the extra money to buy a drive specifically for lightscribe support.