on the charge back up, the apple website doesn't specify whether or not the computer can be on. i can't think of any reason why it would make a difference, as having the computer plugged in and on doesn't draw from the battery. But, is there a common practice to this? Recharge back to full health while the computer is still off, or can i use it while it's getting back to full juice? Thanks guys. I've been wondering for a long while now.