I posted this in the MBP section but maybe this would be a better place to ask this question... I'm running Lion on my wife's 13" MBP and when ever she tries to wake the computer back up after closing the lid with an external monitor plugged in it will not wake. This is an issue since she's a teacher and shows power points all day. If you let the computer go to sleep with the lid open it wakes back up fine, the issue comes if you close the lid and they re-open it while connected. Specs on the machine if that makes a difference is a 2.4 c2d, 4gb of ram, and a 250gb drive.