I have a Mid-2010 MBP running Snow Leopard. Once in a while (this happens about once per week or so) when I shutdown, the menu bar on top disappears, but the dock does not disappear and the computer does not shutdown. I have to force the shutdown (by holding the power button). I went to the Genius Bar (I am still under AppleCare) and the tech said that it seems this is a software issue. They ran tests (the HD, logic board, RAM, everything checked out ok). What are your thoughts? Also, when I shutdown, I have no open programs.