I tried the demo of course and I thought you did a great job. I'm not saying you should abandon the project because of performance issues you'll encounter but rather focus on simplicity with clear boundaries. Again, go for it! (but don't go too far)
I like the concept for graphics-heavy pages, but for any text-oriented page ... well, any website that didn't support highlighting (which I use to keep track of where I am on a page) and that didn't re-render when zooming (absolutely necessary for high-res displays, where a page might show up tiny and need to be re-scaled) would be a website that I didn't stay at for very long.