Back when beta 2 came out I read Scot Finnie's article on ComputerWorld "20 things you won't like about Windows Vista ". I was shocked: with a whole new operating system to aim at he came up with 20 really lame things. I took it as a sign that we'd done really well when 5th place went to "Faulty assumption on the Start Menu.". I don't normally single out people for whining and sarcasm but this stuck in my memory.
In its supreme state of being, Microsoft knows precisely what's best for you. It knows that because its well-implemented new Sleep mode uses very little electricity and also takes only two or three seconds to either shut down or restart, you want to use this mode to "turn off" your computer, whether you realize it or not. It wants to teach you about what's best. It wants to make it harder for you to make a mistake. That's why it crafted the Shutdown area at the lower right-hand corner of the Start menu to make the large red Sleep button and the large blue Lock buttons very prominent. Meanwhile, the button that offers a pop-up menu with options like Switch User, Log Off, Restart and Shutdown is a teeny-tiny little arrow hanging off the edge of the Start menu. They know you'll find it there, but they're making it just a little harder for you to access by making the surface area so small that it's harder to click. So long as Microsoft gets you to do what it wants you to do, it doesn't matter that it's torturing the user experience in the process.
I like to have the power button hibernate the machine, and have it go to sleep if I just close the lid, but with my recent update I found they were both doing the same thing. It took a moment to find it under, Power options in control panel, and click change plan settings, then Change Advanced Power Settings,
you can change a whole range of settings, including changing the default on the start menu. This can be controlled using group policy like the other power settings. If you don't like the default in the beta then give us feedback. If you don't like the default when we ship, now you know what to do to change it.