Actually, the link might not be entirely necessary, as I've seen little pings and flags around SkyDrive cloud documents asking to show off the "preview". But once you enter SkyDrive and enable the preview, it's your default view on any documents you're creating or editing.
It has a nicely pared-down look, consistent with Office 2013, and it's pretty good at showing Word documents in their native style and formatting. If you start needing heavy editing tools, however, you'll see why there's a rather significant "Open in Microsoft Word" button at the top of the toolbar.
What do you think of the Office Web Apps Preview?