My thoughts exactly. Actually when I first saw the video I was really shocked by how ridiculously good the product was and how lacking was the market research/fit. I can only see it suitable for high-end professionals like the Adobe Suite as it is.
I think it should be possible to build very solid apps out of this. They just didn't bothered to develop a polished app as they reply to the YC guys suggests. But they should have, as well as providing video tutorials, documentation, etc...