Before you get too excited, the system doesn't actually reveal other sides of the very object that was in the photo. Instead, it utilizes existing third-party stock 3D models of similar objects, found online. This means that it's currently limited to fairly common items, although more and more such models are being created on a daily basis for use in processes such as 3D printing and animation.
The software assesses the geometry of the existing photo, then manipulates the model accordingly, so the resulting blended image is very realistic. This includes not only altering the model's size and shape (along with that of the original image), but additionally changing its color, surface texture and lighting.