This seems to be tacked on to Flash so I'm curious as to how it compares to Hype (http://tumultco.com/hype/), which is an editor designed exclusively for HTML5.
I've also been making an HTML5 animation design app called Radi [1]. Compared to CSS3-based animation tools like Hype or Edge, Radi is more similar to the Flash Pro environment because it has vector drawing tools and supports more forms of animation (e.g. shape keyframes). Radi also does video.
