Web Application Manifests: Starting in Chrome 39, Manifests let developers wrap metadata about a Web application into a single file, reducing duplication and saving a bit of bandwidth. Adding apps to the homescreen is as easy as defining a title, landing page, default orientation, and multiple icons depending on size and screen density.
When should we as professionals begin implementing this feature? I'm a bit unclear on what it is --- will all websites need to migrate to this, or only "Web Applications." For example would a blog or company info type of website need this in the immediate, or for now is it only for web applications with heavy mobile usage? I see the page references Default Orientation which leads me to believe it's more for Web Apps currently.