ok, so i've had my 15" mac book pro for a little over a year now, and they battery is totaly useless. when i first got it, it would last a little over a class and a half, so a little over an hour. now, it wont even last 10 minutes. i would understand it wearin down over time....but down to under 10 minutes in a year? thats just terrible. and before when the battery ran down, it would just need plugged in and it would come out of sleep mode, and everyhting that was open would still be open. now it shuts totally down and i have to restart it. has this happened to anyone else? does this sound normal or is there something wrong?