Gomes posted a video that demonstrates the various possibilities that adding multi-touch support into a browser could provide, such as image resizing and new ways to play online games. On his personal blog, Gomes also says that CSS support will be added for Web developers via a pseudo-selector, so that if a touchscreen user visits your site, they could be shown special touch only options.
Mozilla provides further details about the API, and how to experiment with multi-touch within Firefox.
Are you excited by the hands-on future of browsing, or do more traditional methods click with you? Sound off in the comments.