By Paul Thurrott
The new Windows 8 shell, as exemplified by the Start screen, works equally well with the keyboard and mouse, or with a Tablet PC-style stylus, as it does with touch. But because a mouse (or a similar device, like a laptop’s trackpad) will be the most commonly used pointing device in Windows 8, it makes sense to investigate how you use one in this supposedly touch-centric UI. Shocker: It works just fine.
Source: Paul Thurott's SuperSite for Windows