From the Microsoft Dynamics NAV Blogs: Windows 8 Jet Reports Player; NAV 2013 Index hinting; Upgrading Reports; Upgrading Commerce Gateway
New Windows 8 Jet Reports Player for Dynamics NAV: The Microsoft Dynamics NAV Team has recently announced that the new Jet Reports Player for Microsoft Dynamics NAV is available from the Windows 8 app store.
The app lets business users to easily download, find, organize and share Microsoft Excel reports and dashboards for Microsoft Dynamics NAV.
With Jet Reports Player users can: View organized report libraries to find the right report for the task at hand. Users can also upload new report library.
You can read about the other features here.