And then there were 6.5 billion

Wired reports that Earth's human population is projected to reach 6.5 billion at 7:16 pm EST today, according to the U.S. Census Bureau and its World Population Clock. That's more than four times what it was in 1900. (Later this year, the population of the U.S. will reach 300 million - approximately what Earth's total population was in the year 1000.)