(Update: 1:43 p.m. EDT)
The royal family has announced the parents have chosen George Alexander Louis as the Prince of Cambridge's names. Still no word on a surname. He will be styled as HRH Prince George of Cambridge.
Original story follows:
As royal baby followers around the world try to guess the Prince of Cambridge's name, they may be forgetting his last name.
Because the royal baby will have the title of Prince of Cambridge, he does not need to have a surname. His parents have three options if they decide to give him a last name.
If Catherine and William want to include a surname, they can choose between Mountbatten-Windsor, Wales and Cambridge.
George V adopted Windsor in 1917 after Windsor Castle, changing it from Saxe-Coburg and Gotha, because of anti-German sentiment in World War I. The Queen and Prince Phillip then combined their surnames to get Mountbatten-Windsor, which was passed on to Prince Charles.
Prince William uses the name of his royal house, Wales, for his military role. The couple could also use Cambridge, the name given them upon their marriage.