A billion. With a “B”. That is how many people on planet Earth will be using the Facebook social network by sometime around August this year.

Facebook revealed at its F8 conference in September that it had reached the milestone of 800 million users. iCrossing, an online analytics firm, has examined the trends at Facebook, and extrapolated the growth to project that Facebook will pass one billion users in August -- August 12 to be precise.

iCrossing says Facebook growth has slowed to a crawl in countries like the United States and United Kingdom. It points out in a blog post, though, that emerging markets are more than making up the difference. According to iCrossing, India has added 14 million users, and Brazil another seven million, just in the past nine months.

Admittedly, “trillion” is the new “billion”, and the capital “B” has lost some of its swagger in recent years. But, when your’e talking about the number of people connected online to a single social network, “billion” still has an impressive ring to it.

Here is some perspective. With a billion users, Facebook would be third in population in the world behind China and India. It would have three times the population of the fourth place country -- the United States. It took the McDonald’s franchise 10 years to sell one billion burgers, but Facebook is on track to reach one billion users in just over eight years.

If Facebook users were dollars, Facebook would have 20,000 times the median household income in the United States (but still a drop in the bucket compared with people like Bill Gates or Warren Buffet). If Facebook users were miles, Facebook would have enough to get to the moon and back…4,000 times. If Facebook users were seconds, Facebook would have almost 32 years of time accumulated.

Based on an estimated worth of $17.5 billion, and the current user base of 800 million, each Facebook user works out to be worth about $22 to Facebook founder and CEO Mark Zuckerberg. If that ratio holds true, Zuckerberg could add another $4 billion or so to his future kids’ college funds this year.

To its credit, Google+, Google’s social network rival of Facebook, has already amassed an admirable user base even at this early stage. Some projections suggest that Google+ could hit 400 million users by the end of 2012. It’s not a billion, but zero to 400 million in 18 months isn’t too shabby.