Ribbon, MVVM and end-user customization

Hi,

I found an older thread about Ribbon and MVVM binding. Is this already implemented?

Also, coming from DevExpress, is there any built-in ribbon/menu/toolbar customization for the end-user?

If not, that would be an awesome feature to have on board. Just like you can do in Visual Studio (customizing menus and toolbars) or in Office (customizing the ribbon).

Regards,
Stefan