Unlike my recent article on Global Using Statement and Code Clues, the new namespace declarations have no trade offs and you should just auto-fix them in your whole project and move on with your life. Here's how we do namespace before namespace declarations:

  namespace Fenton.Sample.UI  {      public class Example      {        }  }

...and here is how we declare namespaces with namespace declarations (no curly braces, no nesting, just a semi-colon):

  namespace Fenton.Sample.UI;    public class Example  {    }

Less nesting, happy days.