The new version, HTML5, already supported by many leading browsers, will enable a whole new generation of interactiveWebapplications and serve as the programming language of the future Web.
Adobe is seeing increasing pricing of its rich Internet apps that are used by Web developers to create rich media webapplications such as online games and interactive visualizations and are superior to typical HTML applications because they allow faster task completion, do not require opening up of multiple applications and are less-error prone.
So, as I read that: Chrome OS is about getting to the browser, which presents the Web richly, and has the store selling applications optimized for a rich interactive environment.