I've had my new SB MBP for a couple of weeks now and have noticed something which I think is odd. The screen automatically dims itself - whether it is running off the battery or the wall plug. I don't see anywhere where I can change this behaviour - the Energy Saver settings mention putting the display to sleep, but not this dimming...it doesn't always seem to be predictable...on AC power it seems to dim after 4 minutes of inactivity, on battery a little less (maybe 2 mins), but sometimes it just does it all of a sudden. I don't know if it would have been relevant, but I did reset the PRAM and I did reinstall OS X. Any thoughts? Could the hardware be defective?