Hi guys I just noticed this problem with my new MBA and it is not limited it. I had the same experience previously with a MBP from work. Whenever I shut the lid to put the laptop to sleep, I had trouble waking it up. It is so hit or miss. Sometimes, if I am lucky I will get the spinning beach ball and the prompt for the password. Upon entering password, the screen goes blank to black and the MBP is back to sleeping with the lid open. Anyway, I am experiencing the same problem with the MBA even though I have yet to set the password function to wake from sleep. It is a most vexing. I would have thought Apple would have resolve this little issue by now. So far my solution consists of a hard reset which means I will lose any unsaved work. Bullocks!