Hmm, the tech is nice, although her voice does sound fake to me (then again, this also applies to Katy Perry, Casha and the likes of them...).
I personally think Jeff Wayne's Richard Burton hologram is by far more amazing. It was modeled after actual photos of the person in question, it has an actual skin texture, and most importantly has more than the standard anime mouth positions "open" and "closed", with slight emotional variations, the graphic representation is actually moved by motion capturing an actual actor:
http://www.thewaroftheworlds.com/features/video-2.aspx
Sadly, I couldn't find a video showing the head in action above the stage.
In case you're wondering why they did that: Richard Burton's voice is seen as an integral part of the whole musical, and since he's dead, he can't play his role himself. That's why they made this 3D representation. The first version was actually a montage of Mr. Burton's head and another actor's mouth and eyes for expression (although blended into each other seemlessly) that was projected onto a simplified styrofoam head, so the viewing direction was fixed. Sadly, I couldn't find any videos showing the new head above the stage, but I guess they'll show up on U-Tube eventually.