I really like the idea and would have to play with it for awhile to really test it usefulness.<p>My feedback:
-it would be cool to add possibility to play with bootstrap or foundation
- You said that it suppose to solve problem of getting mockups quickly online. I am not really sure that is faster than some cloud solution like balsamiq or mockingbird, drag and drop is hard to beat in that departament. It's still YAML ;)
I've been playing with this idea of getting mockups online for clients quickly, so that I can get feedback sooner. So, I built this app. I'd love to hear what people think.