Hi, I have a huge problem with my new aluminum macbook. The battery is running out really fast. Right now I have 80%, the keybord backlight is switched off, the display brightness is set to minimum, I am only using safari and wifi and mac tells me that I have 2:43 more... Normally people write that their new laptop lasts 4-5 hours. Coconut battery tells me that the original battery capacity was 4100 and now it is varying from 4080 to 4130. My macbook has only two days. istat at the begining was showing 4200, now it is 4108... is it normal?