[vmarsy]

Windows Hello uses a combination of special hardware and software to accurately verify it is you – not a picture of you or someone trying to impersonate you. The cameras use infrared technology to identify your face or iris and can recognize you in a variety of lighting conditions.

and later in the webpage:

all OEM systems incorporating the Intel® RealSense™ 3D Camera (F200) will support the facial and iris unlock features of Windows Hello

So by reading this we can assume it does more than 2D recognitions since this is a "3D Camera"

[higherpurpose]

3D models have been created out of 2D images before. I'm not saying this will be hackable from day one, but it will probably take a few short years for a well sponsored and motivated attacker. Hopefully the technology will also keep up and within a year or two we'll see updated versions that make it even harder to replicate.

However, if I were to pick, I'd go for fingerprint recognition instead. Images of people's faces are everywhere online. It's much less likely to have a good photo of your fingerprints.