Latest version of DotNetBar for WPF 5.9 has been released and it follows our DotNetBar for Windows Forms with inclusion of Office 2010 style Backstage support for the Ribbon control. Setting this up is really easy thanks to design-time support we added just for Backstage. Here is screen-shot taken from RibbonPad sample that is included with DotNetBar for WPF install:
You can easily switch between Office 2010 style Backstage Application menu and Office 2007 style Application menu using single property. Click-here to read Knowledge Base article that covers the Ribbon Backstage setup.