Noticing a more than occasional occurrence with my new 12'' Macbook. While running on either power or battery the screen will at times go black. A simple click on the pad usually brings it back to life in the position it was prior but a few times I've had to close the lid and reopen to kick things back in gear. It's almost as if it's going into a screen saver type conservation state but happens when I'm in the midst of working and even with full battery power. Any thoughts?