Impressive attention to detail absolutely everywhere, along with excellent shading to produce that 3D feel. I often feel that these usually come at the expense of cuteness, but not for this piece. That expression is just so adorkable and totally fits Twilight, and it is this expression that really makes this piece stand out to me.
Also, is that scroll documenting scrolls? There seems to be a detailed diagram of a scroll in the lower left hand corner.