Microsoft Published (now it’s deleted), a features overview for developpers
http://www.microsoft.com/learning/en/us/Course.aspx?ID=40027A&Locale=en-us#tab1
• Provide an overview of the new features, functional areas, and product enhancements in SharePoint 15.
• Summarize the key features of the SharePoint 15 application development platform and describe the key features of Marketplaces.
• Explain what a SharePoint-Hosted app is, and describe how to build a SharePoint-Hosted app.
• Explain what a Cloud-Hosted app is, and describe how to build a Cloud-Hosted app.
• Describe how developers extend Office Application user interfaces by creating Agaves and publishing them in different catalogs.
• Describe how to create and code a simple Agave that interacts with document content.
• Describe improvements in Manage Metadata Services, Enterprise Content Management and Web Content Management in SharePoint 15.
• Describe the new social networking functionality available to SharePoint 15 App developers.
• Describe how the new capabilities of the SharePoint Search engine can be used in SharePoint Apps.
• Describe how to query the index from a SharePoint-Hosted app using CSOM.
It’s hard to find knowledgeable people on this topic, but you sound like you know what you’re talking about! Thanks