I think others provide a part of the stack, while we're striving for seamless integration, from concept to publication. Basically, once to bring on others to your game, things get difficult. We want JavaScript developers to write real games.
I had to ask my co-workers to make sure they weren't just giving me a softball question; thanks for the interest :)
So here's the pitch: write real, pro games in JavaScript, deploy to many platforms. Tools for artists, product managers, analytics, the whole she-bang.