Great idea guys! I can already see myself designing something and building a quick real-world prototype and sharing the url of that with clients. So much better than designing/wireframing something, creating a 1000-layer mockup in photoshop, sending over a dozen JPEGS to the client and explaining what's what. As a designer the interface is a nobrainer. I can just step in and get to work. Very easy! Nice to see 960 grids-support as well! I understand there's no liquid-layout support but thats okay. It's not the most important thing. (And I feel you could always add support for that later). One tip: I see the vector-drawing tool and an image import tool. How about vector-import?