I just purchased a Macbook Pro. When I first opened it, it already had a full charge so I waited to charge it after use, instead of doing the "first charge," procedure - essentially charging for an extended amount of time before using. I hope this will not be an issue. It came loaded with stuff for school, so I suppose it was used already anyways (the box was not open). I am not sure how they do this with colleges...? They just have preloaded harddrives maybe? I have used (http://support.apple.com/kb/ht1490) to calibrate the battery. What duration should I be seeing with battery time on the 15" macbook pro?