So I have been wanting a HDMI dongle or similar solution and this sounds promising. I was hoping Chromecast would have delivered something closer to this but alas it focused too much on entertainment content (and tab casting barely works for me).
I know it is a WIP, but this would have been much more attractive/awesome if they managed to power without separate USB and add wifi AC support. That would have made it a serious competitor even if at a higher price point.