The weekend is upon us and that means many operas will be presented around the world. Many theaters will offer holiday presentations while some of the greatest singers return to the stage such as Renee Fleming, Simon Keenlyside, Rolando Villazon, Anna Netrebko, Rene Pape and Nina Stemme. Austria  Simon Keenlyside returns to the Vienna State Opera for Verdi’s “Macbeth” with the {…}