Facebook is fun to use. But it's not a fun place to work — as confirmed by the defection of Net Jacobsson, a key executive in Facebook's effort to cash in on your life online.

"Once every hundred years, media changes," Facebook CEO Mark Zuckerberg said in 2007, predicting a sea change in online advertising. The reality: His social network is leading the way in online scams.

"Facebook suicide" used to mean leaving the ubiquitous social network for the real world. But Paul Zolezzi, an aspiring Brooklyn model, used Mark Zuckerberg's creation to announce the end of his actual life.

Only lawyers and nerds get excited about debating a website's terms of service. And yet Facebook managed to turn a change in its legalese into a PR nightmare. Here's an anatomy of the debacle.

A breathless Fortune story — "How Facebook Is Taking Over Our Lives" — reports that more people use Facebook than watched this year's Super Bowl. Facebook's board of directors must be thrilled, right?

What's Facebook really worth? The fast-growing social network is adding to its 150 million users effortlessly. But revenues aren't growing as easily. And that has Mark Zuckerberg's company tied up in legal and financial knots.

How much did it cost to put a lingering dispute over the creation of Facebook to rest? $65 million, according to the lawyers who hammered out the — oops — confidential settlement with rival ConnectU.

Page Six Magazine is folding, but not before they stroke the egos of anyone who could maybe give them a job with this here list of NYC's 50 Hottest Bachelors. Five problematic entries:

Every generation that logs on thinks they invented the Internet. With Facebook, Mark Zuckerberg may actually have done it. His social network turns five today, and in that time, it has actually changed the world.

After years of freezing out cofounder Eduardo Saverin over a dispute about money, Facebook CEO Mark Zuckerberg has deigned to recognize his former Harvard buddy. Why now? Perhaps to derail a forthcoming Facebook tell-all?

Twitter, the service for posting short updates, has consumed the media elite. Facebook CEO Mark Zuckerberg is privately obsessed with it. By the numbers, though, Twitter is an inconsequential nothing.

What did comedian Michael Ian Black do to get banned from Facebook? I'd like to think it was karmic payback for providing the voice of the Pets.com sock puppet, an enduring icon of dotcom disaster.

With more than 120 million users, Mark Zuckerberg's social network continues to grow, kudzu-like. And yet it is worth far less today than the $15 billion it commanded a year ago. Why is that?

Yes, there's going to be a book about Facebook's creation, adapted for film by Aaron Sorkin, bestselling author Ben Mezrich confirmed. But it won't have lots of sex and cooked Koala, per a Gawker report.

Don Graham, the Washington Post CEO, has joined Facebook's board of directors. Had he not been such a nice guy, he might have had the gig three years ago.

Want a scapegoat for the economic crisis? Mark Zuckerberg looks pretty good right now. Facebook's young CEO dreams of a world where we instantly know each others' emotions. To our peril, we're already pretty close.

So much for Silicon Valley's latest get-rich-quick scheme. Facebook CEO Mark Zuckerberg has cancelled a plan to let employees cash out their shares early.

Social networks have a lifecycle: They start with a small core of early adopters, swell as mainstream users get pulled in by their friends, and then see growth taper off as people get turned off by spam. That's why Friendster is forgotten and why MySpace is looking increasingly stagnant. The price for reaching an audience advertisers care about seems to be a site users can't stand. Facebook, however, isn't following the fashionable trend.

Through the golden heart of every world-changing startup pulses an avaricious get-rich-quick scheme. Larry Page and Sergey Brin, the billionaire-boy cofounders of Google, established this doing-well-by-doing-good myth. But Mark Zuckerberg hasn't been able to make the same magic happen for his employees. In his efforts to make good by them, he may end up quashing a nascent market in Facebook shares.It's not for lack of trying. Silicon Valley's stock-options millionaire make money by getting the right to buy shares at a low price and selling them for a higher one. Facebook's soaring valuation — Microsoft invested $240 million for a tiny stake, in a deal which valued all of Facebook at $15 billion — threatened to undo that equation. How is Facebook supposed to soar past $15 billion in value? So Zuckerberg & Co. turned to issuing restricted stock units, or RSUs, instead. (Restricted stock units are common at large companies like Google and Microsoft, but unusual for a company Facebook's size and age.) The restricted-stock plan has created a new complication: Once it has more than 500 RSU holders, SEC regulations may require Facebook to start publishing its financials, even if it doesn't conduct an initial public offering. Facebook's revenues still aren't pretty enough for public exposure. Facebook's lawyers have sought, and obtained, an exemption. Part of the argument they made is that issuing RSUs won't create a market in Facebook shares. Facebook, unusually for most of Silicon Valley's private companies, has not had many restrictions on what employees and other shareholders could do with the shares they own. Most have rules that force shareholders to offer shares to the company first — a right of first refusal — or outright prohibitions on unauthorized sales. But the letter Facebook sent to the SEC says that even when the stock units convert to common shares, they have limits on their sale: "... the Plan has been structured to preclude any trading of RSUs or any interest therein from developing." Even if Facebook permits an employee convert their stock units to shares and sell them, the company can then prevent the buyer from selling. Employees at Facebook — especially the early ones, whose holdings are now substantial — have been agitating for some time to sell their shares, and there are still, even with the public markets taking a beating, interested buyers. Zuckerberg finally bowed to this pressure and set up a program, now underway, to let employees cash out up to $900,000 in shares. (Note the symbolism of the figure: No one will become a millionaire.) But that may be it. If Facebook extends its stock-sale restrictions to common shares, not just the restricted-stock units, both employees and the investors so eager to snap up their shares will be stuck, until Facebook sells out or goes public. Zuckerberg has made it clear he thinks both of those events are far off — and the 24-year-old CEO still owns 27 percent of the company and more or less controls the board. It's a dicey gamble. The prospect of selling Facebook shares privately must surely have attracted some employees who counted on a relatively quick cash-out. But shutting down the prospect of further stock sales will make sure the Facebookers who remain will be more committed to the company for the long haul. Zuckerberg doesn't have much choice. As long as Facebook employees can find buyers for their shares, they'll be tempted to leave rather than stay at a company going through a tumultous adolescence. Already, the company has had far more turnover, from bottom to top, than Google did. Not a single high-ranking exec left Google for the first six years of its existence. Facebook has lost three of its four cofounders, and numerous people underneath them, from former COO Owen Van Natta on down. No wonder Zuckerberg wants to slam the exit door closed.

Why have social networks blossomed in as antisocial an environment as Silicon Valley? Because they allow computers to become a crutch for a task most engineers find imposing: dealing with other human beings. Turning relationships into a social graph that can be fed into a database and ruled by algorithms is a genius move for tech's clumsy savants. Alex French, a writer for GQ, interviewing Facebook CEO Mark Zuckerberg for a profile, wonders if his cold stare and cagey responses are an incredibly calculating attempt to intimidate, or merely a sign that he's awkward. Either way, Zuckerberg shows a disdain for displays of emotion. Asked if he celebrated Microsoft's $240 million investment in Facebook, Zuckerberg seems puzzled by the question's premise. And yet emotion is at the core of Zuckerberg's plan for world domination.In a conversation — conducted on instant messenger, the computer-moderated communications mode of choice for the socially impaired — Zuckerberg reveals that he hopes Facebook will one day broadcast its users very emotions. French probes him on this issue in the following exchange: