I recently posted my experience upgrading my Aluminum MB's HD to a Seagate 320gig 72000rpm...it's easy as pie so to speak. But I noticed recently that my battery empties faster than normal. I have not calibrated it yet so it might get better after doing so. This is my first HD upgrade on a laptop so I am not really sure. Although logic seems to point to this being the norm...what do you guys think?