Sofia Vergara and Joe Manganiello spent their New Year’s Eve in Las Vegas, where they caught a performance of Britney Spears ‘s “Piece of Me” show at Planet Hollywood. They were joined by Arnold Schwarzenegger and his girlfriend Heather Milligan in the audience. Sofia and Joe, who got engaged on Christmas Day , recently returned from a Hawaiian getaway to celebrate Joe’s 38th birthday. It was an exciting 2014 for the couple and it looks like 2015 might have even more in store!