Quite new to the mac world, just been using my 2.6ghz MBP for about 3 weeks and the battery health is down to 98% after 8 charges. Forgot to calibrate it when i first got it but was doing it now. Just a quick question on the process though... So having charged it over night and let it sit ive unplugged it and am using it, but during running the battery down can i shut it down and start it up again, or should i leave it sleeping, or should i not turn it off at all and make sure that im using it at all times until the battery is empty?? Thanking you. Wozza.