I have yet to totally discharge and charge my new PB's battery. I have also noticed that my 12" latest revision PB gets quite hot when just using safari and possibly adium and iTunes. I have read that calibrating the battery is a possible fix to the heat. Can anyone confirm that? My widget temp readings aren't very high, but this thing just feels really hot to my left palm -- I have a nice little 1/4 of a first degree burn mark there every now and then .