The most important thing to keep in mind is this is for designers not coders -- I haven't looked at this deeply enough to know if it is good yet, but my guess is if you read hacker news comments it isn't for you because, well, you probably code=).

Yes, these sorts of editors often create horrible leaky abstractions. Yes, these editors often confuse product folks into thinking that coding isn't necessary or important or hard. But that isn't its goal -- the goal is to make the common stuff easy to do for people writing / designing simple site content -- fades, positional, simple triggers. There is no reason to write code for this stuff.

If you don't believe me, imagine drawing something without showing the picture. Word documents without wysiwyg. Photo editing without Photoshop. In this video (http://vimeo.com/64895205) Bret Victor brilliantly shows what a powerful interactive editor can do. For the web, no amount of manual css typing can beat what a great editor could do. Whether this is that editor remains to be seen, but the idea of editors is a good one.