ExtendedTextCell - Text not appearing?

I am trying to use the Xamarin.Labs ExtendedTextCell in a list. In the following simple code, the list binds to the correct number of cells, but no text is displayed. Am I missing something simple here?

        var itemTemplate = new DataTemplate(typeof(ExtendedTextCell));
        itemTemplate.SetBinding(ExtendedTextCell.TextProperty, "Text");

        var list = new ListView()
        {
            ItemsSource = new List<ExtendedTextCellItem>
            {
                new ExtendedTextCellItem(){Text ="Global Indicies", TextColor = Color.Blue},
                new ExtendedTextCellItem(){Text ="Energy (USD$)"}, 
            },
            ItemTemplate = itemTemplate  ,
            HasUnevenRows = true,
            VerticalOptions = LayoutOptions.FillAndExpand
        };

        Content = list;