I own a 13" MacBook Pro since late July. I will always put it sleep by closing the lid. Many times it will not awake when I open the lid again. The sleep led stops blinking, but the display stays black and the keyboard lights stay out. Closing an reopening the lid does not help: the MBP will not awake from sleep anymore. The only thing that helps is a hard reset. I tried resetting powermanagement and have also been experimenting with the various sleep mode settings. This sometimes seems to work, but after I while I keep experiencing the non-awakening again.