Pew released its research on the demographics of social media users for 2012. Jim Romenesko put them together in a pithy breakdown. Two-thirds of adults who use the Internet use Facebook, which was way ahead of all other sites. Sixteen percent are on Twitter, doubled from November 2010. Young people are more likely to use Facebook and Twitter, and women are more likely to use Facebook than men. Pinterest attracts more white people. Instagram has more African-American and Hispanic users than whites. Though Tumblr brings up the rear with only 6 percent of Internet users, it’s much more popular among young people, with 13 percent of 18- to 29-year-olds online signed up.