Burchill found this while sifting through the Consumer Preview bits:
Update: This might not be as promising as Burchill originally thought. He has amended his post to note that this setting may be a server-only thing.
While many love the tiled Metro start screen and are looking forward to using it on touch tablets and PCs, many others aren’t keen on it — especially business users who are convinced that Metro will be nothing but a nuisance, especially on non-touch-enabled hardware, and that they’ll do most of their work in the Desktop app on Windows 8.
Read on at ZDNet