Wow, this is one of the coolest projects I've seen recently on HN. I'm not sure why it didn't garner much attention, but I think the concept is clever and the implementation is great. Here are some random thoughts:

- I knew the purpose immediately upon page load

- extremely easy to use

- controls are very intuitive and fun to play with

- preset colors are appealing and easy to adjust

- email field and message field are ridiculously simple to add/remove and look fantastic

- only usability issue: text does not center properly and I'm not sure why the text fields for the welcome message are re-sizeable (running Chrome browser)

From a developer's perspective, it really seems like you put a lot of thought into the user interface. A user who is not tech savvy would probably have a painless time maneuvering about your site and understanding the product, which is definitely one of the most difficult things to accomplish when building a web app for non-technical demographic. That being said, I just re-read your description and it looks like you may be targeting the hacker crowd, which I think is a mistake. Any decent developer (or designer) can hack together a "coming soon" page without very much effort. Also, I don't think this warrants a $9/mo pricetag, regardless of the target demographic. Perhaps you should toy with the freemium model and see how that works out.

Keep up the good work!