I calibrated my battery on my new Macbook Pro 1,83 exactly according to instructions, even let it sit in sleep overnight after it ran out before recharging. Before I got almost 4 hours and way over 3 with light use and display at 50%. Now I get way less than 3 with lower settings, even tried with just one core running. Any idea what is going on? Anyone else had the same problem? I will never calibrate a new battery again until I see an issue with it!