Looks great! The two-cursor feature would also be extremely useful when two mice are connected to one computer. We do pair programming at work and I could see a tool that allows two people sitting at one machine to each have their own cursor totally transforming the way we work. Is this a feature you plan on developing?

We've found that since we've starting using PowWow, we don't need to sit at the same computer when we're working together. In fact, we prefer to stay at our computers, even if we're sitting next to each other :) Being able to use our own screen, with our own particular hardware setups is really nice. It also avoids having to reach over the other person to use the keyboard, or squint at the screen because it's too far.

I like this technique, and I think it would be appropriate to extend it other hierarchical types of data besides just text. For example, a product page might show a list of reviews, with each shown as x/5 stars, and zooming in on the reviews would show the review text. Same with product info - zoomed out = overview, zoomed in: more details appear. This would require zooming in on a specific section of a page though, not just making the entire page bigger. Imagine browsing an online store or search results by zooming in/out using a touch interface, rather than clicking on links to details/reviews/photos