Adam Ostrow over at Mashable posted new numbers from Nielsen Online on the popularity of Facebook. For November 2008, Nielsen reports MySpace having 59.1m US visitors and Facebook having 47.5m US visitors. This is pretty amazing growth with FB up from 39.9m visitors in October 08 and well above 21.9m US visitors in November 07. The chances are good that FB will pull ahead of MySpace in 09.