If you’re a developer for a document storage system and you’d like to use Office Web Apps with that system, we have what you have been waiting for!  Well to be more specific the Office Developer blog has it!  The Office Developer blog post Introducing WOPI describes how to create a WOPI host—which is basically a software solution that can take advantage of the browser-based Office file viewing and editing services that Office Web Apps provides. 

Once you create a custom WOPI host, you configure it to use Office Web Apps Server to provide the browser-based file viewing and editing services for Office files. To learn more about Office Web Apps Server, see our previous post Introducing Office Web Apps Server and the TechNet article Office Web Apps Server Overview.

To find out how you can create your own custom WOPI host, see the Office Developer blog post Introducing WOPI.