After a few critical reviews on the net to Scorpio Black 320GB and 500GB in Macbooks / vibration and noise, I was not sure if the hard drive in exchange for the standard Hitachi 320GB would be the right choice for me - and did so in addition to the WD Scorpio Black 750GB also the WD Scorpio Blue 1TB ordered in order to obstruct my Macbook Pro at "not satisfied" the WD Scorpio Black 750GB.
After installing the WD Scorpio Black 750GB I have transferred the entire contents of the Hitachi 320GB with Copy Cloner from an external HD and then worked a few hours with the new constellation.
My first impression now: the Western Digital Scorpio Black 750GB is very fast, does not develop any vibrations and of a "noise" is definitely not to speak! The hard drive works just whisper as already the Hitachi 320GB has been doing its job - and here I consider myself personally very critical!
The WD Scorpio Blue 1TB I will now return untouched - the WD Scorpio Black 750GB is highly recommended!