You can check out via a Android or iOS based product at:

If you try via the desktop you get a unsupported message: (not sure why? I guess they want you to experience the touch concept...which is silly since I would think their main target would be users who don't already have a Android or iOS based product.

I test drove it on the iPad in landscape mode and it tells you to flip it to portrait. This is done via CSS and can be tested as shown.

Flipped into portrait mode and got started, here's some sample. Nicely done Microsoft.