A lot of people say that Facebook has jumped the shark. That’s flat out wrong. In fact, Facebook is now being devoured by the shark. There’s so much blood in the water, it’s attracting other sharks. And if Facebook’s not careful, one of them is bound to come along and finish it off. I’ve never seen anything like it in the annals of fast-rising tech companies that fail.

The really weird part of this story is that there’s absolutely nothing wrong with Facebook. It works as well as it ever has, and many of the people who use it (my kids for instance) are unaware of the worsening situation about its privacy-invading Beacon social ads scheme that tracks people’s web-surfing habits even when they’re not on the site. That’s bound to change. The market is fickle, something better is in the wings, and as soon as it arrives, the alienated and angry mob will race to it. Delphi’s errors begat Prodigy and its errors begat AOL, which was crushed by the Web.

What’s surprising here is the speed with which this thing is coming undone — and the ease with which it could have been avoided. What’s harming Facebook – perhaps to a terminal degree – is enormously bad PR. For a social media company, these folks don’t understand the first thing about communication; they have alienated the press by being arrogant, aloof and dishonest. Their idea of press relations is sending a stupid message to a What’s New at Facebook Group that directs you to another website for a canned statement.

And it is killing them. That bad press extends from the blogosphere to mainstream media. No one who writes about Facebook likes it anymore. And while that might seem insidery — who cares what the press thinks? — it’s having dire repercussions. For one thing, advertisers care what the press thinks. Bad press is causing advertisers to jump ship. And that’s begetting even more bad press. It’s the opposite of a virtuous circle; it’s an economy being undone.

It could have all been avoided with a smart adult running things. Facebook has no old hands in its corner, no advisers to tell the kids how to behave. Netscape had its Jim Barksdale, Google (GOOG) its Eric Schmidt. This company has no one babysitting it. And watching it now is like watching an unattended child play with a pack of matches in a wooden house.

Facebook’s problems are well known. They started when young Zuckerberg stood up and made preposterous statements to Madison Avenue — who let him say that stuff? What genius wrote those immortal lines and had such a tin ear for how it would play? The situation worsened when the company compounded its hubris with lies. Its ongoing contempt for the press and disregard for the First Amendment doesn’t help. And now, it has no one in its corner that anyone in the media trusts.

Facebook has turned all the people who rooted for it into a lynch mob. In the space of a month, it’s gone from media darling to devil. The most interesting thing about Facebook right now is who will replace it.