I've had my 2010 17" Macbook Pro for about a week, during which time the computer has been used about equally plugged in as battery only. I've also done a battery calibration by running the computer until sleep, letting it sit overnight, and then charging it back up the next day. I've noticed that the 'battery health' as reported by the iStat widget has been steadily decreasing. While it started at 99%, it's now (and keep in mind this is only after one week of use) at 95%. Has anyone else noticed their computer's battery health deteriorate so quickly? should i be concerned about this? Thanks!