If you go to Google Maps and look at the Pegman used for browsing street view images, you will see the Pegman is wearing a Santa hat.
The Santa Pegman is not new, it was shown to us when Google had a welcome back party for the Pegman in the new version of Google Maps.
Plus, Google has had the Pegman wearing a Santa hat since Christmas 2010.
Hat tip to Alex Chitu for spotting this.