A little disturbing, rather uncanny valley, but surprisingly realistic. We've all seen the websites that have cartoon people watching you (your mouse) and now it's been taken to the next level with a virtual girl watching your mouse!
There's no information on the page so I can't say who made it, why they made it, or how but I can make some educated guesses. The head uses a flash 3d system with some sort of bone or morph based animation code. The eyes are separate meshes and so can move independently. The bones/ morphing gives the face the ability to blink, and the head to turn.
Found via JazJaz