Part of the problem is that the web content and security model requires one to consider a domain somewhat isomorphic to an app. It wouldn't be so bad if the te

Part of the problem is that the web content and security model requires one to consider a domain somewhat isomorphic to an app. It wouldn't be so bad if the technology existed to reliably say "foo.com is serving data that can be rendered via the some-standard-component presentation layer." Then, the browser itself would have the capacity to cache and optimize the rendering layer for common content schema. As it stands, your choices are to code to one schema (the HTML5 / CSS / no Javascript presentation standard, with all the restrictions that implies), to write a web app that will be a special little snowflake different from all the other special little snowflakes on the web, complete with its own chunk of memory and processing in your browser, or to throw up your hands and commit your content to one of the existing solutions that build the app for you (but then basically also control your data). We're missing a functional division between data and app that we have in the desktop model.