Facebook is tight-lipped about its revenue numbers, which is typical of private companies. The most it has said publicly is that it became “free cash-flow positive” as of last September. At the time, we estimated it was set to bring in around $550 million for the year in revenues based on previous reports that we and others had heard, and from our own calculations. But how did the year actually end? Somewhat higher. And sources estimate the company could make between $1 billion and $1.1 billion in total revenue this year.