The Facebook juggernaut has run out of steam in the U.S. According to Nielsen Wire the unique visitors has settled in between 130M and 135M per month (lower than the ComScore data in the graph below) and time spent on Facebook each month continues to decline.
What growth there is in the U.S. is with retirees and pre-teens with a net loss of users in the 20-something demographic - basically the early adopters of Facebook are bored with it and have moved on now that their Grandparents signed up.
If you have been on Facebook more than 1 year, do you spend more time on Facebook now than you did a year ago? How often to you post to Facebook every month now compared to one year ago? (If you are selling social media consulting and services keep in mind your answers are probably well outside the norm)
http://tommytoy.typepad.com/tommy-toy-pbt-consultin/2011/03/facebook-reaching-max-penetraton-in-us-growing-internationaly-will-definitely-not-hit-1-billion-user.html