I have a unibody Macbook Pro that is less than two weeks old. I've gone through a couple of battery charge cycles. When I first got it I let the battery drain down to zero and then let it stay that way for about 5 hours before plugging it back in. Once I plugged it in, I let it charge overnight. Today, I noticed that my MBP shows the battery level at 99% after being plugged in all day. I'm not terribly concerned but I'm curious as to why the level is not at 100%. Is this normal?