I stumbled upon more public stupidity today, this time, over at Venture Beat. Writer Jordan Novet parroted a claim that "Facebook ... now boasts 1.28 billion monthly active users." 

Right now, the U.S. Census Bureau estimates there are 7.175 billion on the earth. If Facebook had 1.28 billion monthly active users, that would be almost two of every 10 on earth were logging into Facebook to show off pictures and brag about their summer vacations paid with HELOCs.

Do you believe that 2 of every 10 living in India checked into their non-existent Facebook account today with the computer or smartphone they don't own and the Internet access that doesn't exist?

Do you believe that 2 of every 10 living in western China checked in last week?  Do you believe that 2 of every 10 living in the many countries of Africa checked in only this morning? How about those tribal ones living in the jungles of Brazil or maybe Papua New Guinea, did 2 of 10 of them check into their Facebook account to write a timeline update the other day?

According to SocialBakers, about 4% of Africans used Facebook at all in 2013. Africans constitute 15% of the world, or roughly 1.5 in 10, which when rounded to a whole person is 2 in 10. So 4% of Facebook-using Africans would count up to a puny 4 in 100. 
So where are those 16 Africans supposedly using Facebook?

SocialBakers also reports 247.7 million Asians using Facebook. That comes to 5.7% of all Asians. Said another way, that is 6 out of every 100. So where are the missing 14 Asians supposedly using Facebook?

Asians comprise 60% of world population. Together, Asians and Africans comprise 75% of world population. 
Using numbers from SocialBakers and Wikipedia already cited, total Facebook users constitute 12.7% of world population. That comes to 13 in 100 or roughly 1 in 10. And while that seems impressive, again, how many of those accounts never fire up a view on Facebook but only use Facebook to log into other web sites?
A reasonable estimate would be closer to 138.1 million log ins monthly with about 75% of those logging in to use Facebook credentials elsewhere. Even that might be outrageously high.