I've seen several blog posts on pinning shut down, restart, sleep, etc, shortcuts to the new Start Menu ("Start") but having separate icons for each function seems a bit of wasted screen estate. I then found someone suggesting pressing "Windows+D" to minimise to the desktop and then pressing "Alt+F4" to bring up the Shut Down dialog.
From this I've created a simple AutoIt app that will show the “Shut Down Windows” dialog:
To use, extract the .exe, save it somewhere and right-click “Pin to Start”
Then drag the icon to where you want it on your "Start" (Menu)…