First time poster. Got my sp2 yesterday and after a bumpy start am using it. It was a bit of a stressful purchase. I'm not an early adopter by any means. One of the reasons I made the move was my old laptop is an XP one! One of my big worries is the battery and potential cost of replacement. I'd like to put that off as long as possible! I've done some searching to learn as much as I can about these batteries but have some questions. 1. When plugged in, does the computer run on the battery or the power source? OR when plugged in is it simply charging the battery? Would keeping it plugged in as much as possible when using extend some of the battery life? I've read to do the following, as well: Let it run below 10% once a month. Try to only let it charge to about 80% Anything else? TIA.