I use swype now and am extremely happy with it. I can't imagine this would be any better than it. With swype, I can enter n characters with a path of at most n vertices, with this thing, it seems I need to create n differently-sized arcs. Swype also has zero learning curve, assuming you know qwerty, because you can use it as a touch keyboard by default.

It's not clear if the finger needs to be removed between letters (but I doubt it does). This would worry me.