I have a MBP 2.2Ghz from Sept 2007, reaching almost one year since purchasing this unit, and have kept it on most of the time since then, putting it sleep or sometimes shutting i down for a aday or so at a time over the course of hte past year, and im just wondering some good thorough tips to keep the battery n good health. iStat Pro indicates the battery is at 91% health and im not sure if thats good or not for a one year old system. i usually let it drain itself then plug it in and repeat that cycle. somtimes its usually plugged in most of the time, even at full health, but have been trying to reduce that habit to keep the battery flowing. so is the 91% healthy for a standard usage and one year old system? thank you!