Due to privacy constraints, we won’t know exactly who that is, or where; and there’s no prize waiting for him or her.

The site, which launched in 2004, has gained around 100 million new users in the last six months.

Nonetheless, those numbers generate some huge and interesting statistics in the aggregate. Facebook users have uploaded 50 billion photos (and tagged 15 billion of them). Einstein, Twain, Wilde, Gandhi and Shakespeare are among the most quoted people on profiles.

Nearly 20% of users list themselves as single, about 16% as married. Members create 400,000 events each day

Yet one of the most interesting aspects of the community for Randi Zuckerberg, who does marketing for Facebook (and is founder and CEO Mark Zuckerberg’s sister), is what has stayed constant through the growth spurt. For example, “even back when we had one million users, Harry Potter and The Bible were the most popular books,” she says. “500 million later, Harry Potter and the Bible are still there.”

Facebook has grown up since it began as a haven for only a few select universities in 2004.

About 70% of Facebook’s users now live outside of the United States, with the Middle East, Indonesia, Malaysia, Singapore, India and Brazil becoming some of the fastest growing regions.

“It has changed in a lot of ways,” Zuckerberg says. “Instead of looking at Facebook as a tool to look up other college students, you really feel like you can look up almost anyone in the world.”

“Mobile is fast-becoming our growth lever,” said Erick Tseng, Facebook’s head of mobile products, at Venturebeat’s MobileBeat conference earlier this month. “As we begin to continue to expand, we’re starting to go into geographies where phones are the predominant way you access the web. Mobile is a way we can get users to be aware of and engage with social services.”

As for Facebook Stories, the to-be-unveiled service will serve as a launching ground for the various user stories that Facebook users have been submitting to the site. Up until this point, user tales have been individually featured as part of the “Your Stories” section of Facebook’s official blog.

Facebook Stories, in contrast, will feature organized the submitted, 420-character-or-less anecdotes by geography or theme—like, “finding love,” “coping with grief” and “natural disasters,” reports Swisher. Users will be able to link their stories to their Facebook profiles and, naturally, Facebook’s 500-million user base will be able to comment on and “Like” the stories as they see fit.

Facebook said the number was “an important milestone” and added that it was “humbled and inspired” by the stories of its users, which it is asking people to share on the site.

Maybe the next milestone, which will probably be 750m, won’t take so long…

According to the technology blog TechCrunch, Elevation Partners, the private equity firm backed by bad-backed U2 frontman Bono, has stumped up $120m for just over 0.5 per cent of Facebook.

The deal values the dominant social network at $23bn, and takes Elevation Partners’ total stake to 1.5 per cent, having invested $90m at a $9bn valuation last year.

Reports earlier this month claimed Facebook’s sales were between $700m and $800m last year, so Bono and friends reckon it’s worth about 29 times revenue at the moment. Which is a lot.

Elevation Partners mission is about helping media and entertainment entrepreneurs develop and deliver content, leverage new platforms and channels, namely social networks and social media assets.

Facebook is still growing at an incredible rate, and recently hit 500 million users, further fueling hopes that the still private company might seek to go public sometime soon, but most IPO observers have said they don’t expect Facebook to file anytime this year, even if the market gets a slight psychological boost from the Tesla Motors Inc.IPO on Tuesday.

So Elevation probably will likely be holding its investment for awhile.

Venture Beat reports also that Bono Vox has invested on its own too in the social network, in addition to the Elevation Partners deal, along with founder Roger McNamee, showing a strong confidence in Zuckerberg’s idea and project.

More info are available here and here.

Who’s Blogging What now gives an opportunity to delve deep into Facebook Page Marketing.

The 30-page guide has truly interesting (albeit not completely new) tricks&tips regarding the Facebook Page arena; a recommended reading is Getting People To ‘Like’ Your Facebook Page by Lisa Barone.

You have to make people want to join your Facebook page.
It’s simple: You can’t market to or build brand awareness with someone who’s not opted in. What’s not simple is getting a user to hit that ‘like’ button. Users are a lot more discerning on Facebook than on other social sites. For them to opt into your page, they need a compelling reason. It’s a big step from passively liking a brand to publicly ‘liking’ them in full view of friends and colleagues. You have to make it worth their while.

That’s as simple as it seem even though a tough goal to reach.

Get the Facebook Page Marketing Guide by clicking here, it’s free, it’s fun and may be useful too.