When you slam the lid down, does your computer go to sleep or it still runs? It happened to me on Preview 1 that the entire machine was still running even when the lid is closed. I got tired of having to shut down my computer all the time and decided to go back to Snow Leopard, because I'm consistently mobile. I just downloaded Preview 2 from MAS, but still unsure if I should install it since this is the biggest issue I ran into. Somebody please confirm.