http://www.pcworld.com/article/251022/windows_8_consumer_preview_keyboard_shortcuts.html

Hotkeys unchanged from Windows 7 
Key combination Windows 7 functionality 
Windows Display or hide the Start menu. 
Windows-Left Arrow Dock the active window to the left half of the screen (does nothing to Metro-style applications). 
Windows-Right Arrow Dock the active window to the right half of screen (does nothing to Metro-style applications). 
Windows-Up Arrow Maximize the active window (does nothing to Metro-style applications). 
Windows-Down Arrow Restore/minimize the active window (does nothing to Metro-style applications). 
Windows-Shift-Up Arrow Maximize the active window vertically, maintaining width (does nothing to Metro-style applications). 
Windows-Shift-Down Arrow Restore/minimize the active window vertically, maintaining width (does nothing to Metro-style applications). 
Windows-Shift-Left Arrow Move the active window to the monitor on the left (does nothing to Metro-style applications). 
Windows-Shift-Right Arrow Move the active window to the monitor on the right (does nothing to Metro-style applications). 
Windows-P Display projection options. 
Windows-Home Minimize all nonactive windows; restore on the second keystroke (does not restore Metro-style applications). 
Windows-number Launch or switch to the program located at the given position on the taskbar. (Example: Use Windows-1 to launch the first program.) 
Windows-Shift-number Launch a new instance of the program located at the given position on the taskbar. 
Windows-B Set focus in the notification area. 
Windows-Break Display the System Properties dialog box. 
Windows-D Show the desktop; restore on the second keystroke (does not restore Metro-style applications). 
Windows-E Open Windows Explorer, navigated to Computer. 
Windows-Ctrl-F Search for computers (if you are on a network). 
Windows-G Cycle through Windows Desktop Gadgets. 
Windows-L Lock your computer (if you're connected to a network domain), or switch users (if you're not connected to a network domain). 
Windows-M Minimize all windows. 
Windows-Shift-M Restore minimized windows to the desktop (does not restore Metro-style applications). 
Windows-R Open the Run dialog box. 
Windows-T Set focus on the taskbar and cycle through programs. 
Windows-Alt-Enter Open Windows Media Center. Note that Windows Media Center must be installed for this key combo to function; in many Windows 8 builds, it is not present. 
Windows-U Open Ease of Access Center. 
Windows-X Open Windows Mobility Center. 
Windows-F1 Launch Windows Help and Support. 
Windows-N Create a new note (OneNote). 
Windows-S Open screen clipper (OneNote). 
Windows-Q Open Lync. Note that in Windows 8 the Search function overrides this key combo. 
Windows-A Accept an incoming call (Lync). 
Windows-X Reject an incoming call (Lync). Note that this key combo does not function if Windows Mobility Center is present on the machine. 
Windows-Minus Zoom out (Magnifier). 
Windows-Plus Zoom in (Magnifer). 
Windows-Esc Close Magnifier. 
    
New hotkeys for the Windows 8 Consumer Preview 
Key combination Windows 8 functionality 
Windows-Space Switch input language and keyboard layout. 
Windows-O Lock device orientation. 
Windows-, Temporarily peek at the desktop. 
Windows-V Cycle through toasts. 
Windows-Shift-V Cycle through toasts in reverse order. 
Windows-Enter Launch Narrator. 
Windows-PgUp Move the Start Screen or a Metro-style application to the monitor on the left. 
Windows-PgDown Move the Start Screen or a Metro-style application to the monitor on the right. 
Windows-Shift-. Move the gutter to the left (snap an application). 
Windows-. Move the gutter to the right (snap an application). 
Windows-C Open the Charms bar. 
Windows-I Open the Settings charm. 
Windows-K Open the Connect charm. 
Windows-H Open the Share charm. 
Windows-Q Open the Search pane. 
Windows-W Open the Settings Search app. 
Windows-F Open the File Search app. 
Windows-Tab Cycle through apps. 
Windows-Shift-Tab Cycle through apps in reverse order. 
Windows-Ctrl-Tab Cycle through apps and snap them as they cycle. 
Windows-Z Open the App Bar. 
Windows-/ Initiate input method editor (IME) reconversion. 
Windows-J Swap foreground between the snapped and filled apps. 