BREAKING NEWS! 6TH UPDATE: Jeff Zucker decided to reveal this morning he’d been fired by Comcast because he’d just finished negotiating his severance package, insiders explain to me. So Zucker told reporters that the decision for him to leave as head of NBC Universal was made for him by Comcast COO Steve Burke 2 weeks ago during a face-to-face meeting. “He made it clear that they wanted to move on at the close of the deal and I was completely comfortable with that,” Zucker told his favorite journalist, Bill Carter of The New York Times. “We had both gotten to the same place.” It has long been expected that, once NBCU switched out of GE’s control where Zucker was inexplicably protected by CEO Jeffrey Immelt,  the savvy Comcast brass would recognize how badly the NBCU topper had “Zucked-up” his job. (I scooped how, during Zucker’s mishandling of the Conan O’Brien-Jay Leno Tonight Show situation, private emails went out from high-level executives at Comcast saying, “What a mess.”)

But General Electric, a company that used to prize only excellence, kept rewarding Zucker’s failures. Then again, Zucker was embarrassingly proud that he kept managing for margins, not programming for ratings. So NBC eventually stood for Nothing But Crap. When he got beat up by the media, he decided that the company should go to DEFCON 1 (the defense readiness condition representing expectation of an imminent attack) and set up a PR War Room filled with flacks to fight back. As a way to cover his ass in the event Comcast did kick him to the curb, Zucker earlier this year bizarrely sent up a trial balloon that he might run for public office instead of run NBCU. Now that he’s odd man out, no one is taking up a collection: Immelt bestowed on Zucker a new 3-year contract so Comcast had to negotiate a rich payout.

Zucker told senior staff later this morning it would be “business as usual” for him until Comcast took control of NBCU. But he ran to whine to NYT‘s Bill Carter, who’s generally recognized as a suck-up to network moguls. (Carter is writing a book about the Late Night Follies involving Conan O’Brien and Jay Leno and David Letterman that’s a sequel to his Late Shift. So the NYTimesman had worked overtime to ingratiate himself with Zucker.) Today, the NBCU chief described his forced exit as both “incredibly emotional” and “gut-wrenching” because he’d spent half his life at NBC. In previous interviews with journalists, Zucker had demonstrated considerable bravado and misplaced arrogance that “of course” he would run NBCU after Comcast took control of 51%. (He even made a bet with me that he’d still be NBCU’s media mogul two months after the merger. Hey, Jeff, I win!)

But today, Zucker backpeddled. “Look, I knew from the day this was announced that this was a possibility,” he told Carter. “I wasn’t going to shut the door on anything. But in the last nine months it became increasingly clear that they did want to put their own team in place — and I didn’t want to end up being a guest in my own house.”

What’s incredible, and demonstrates how much he’s still in denial, is that Zucker told Carter he did not detect “any particular reason” for Burke firing him beyond Comcast’s wanting to make a change.

There is no doubt that Zucker’s legacy in Hollywood will be as one of the most disliked executives ever to head a Big Media company. His rival moguls laughed at his humiliations. The agents and managers and lawyers treated him like a buffoon. Even his own NBC show 30 Rock and anointed late night comic Jay Leno made jokes at his expense every chance they got. And each time he made an error in judgment, which seemed like all the time, he never paid a price for his mistakes, which made ”Zucked” and “Zuckered” part of the media lexicon. That’s also why Zucker earned the moniker, ”Teflon Jeff”.

Zucker’s firing followed what I reported was a “charm offensive” he launched back in May. The NBCU chief tried to demonstrate he was a new and supposedly improved Zucker, a nicer Zucker, and not the thin-skinned humorless bully of a boss which the journalism and showbiz communities have come to know and dislike and ridicule. ”He’s being so nice to everyone, so friendly, a more lovable guy,” one top TV agent described Zucker to me after Universal boss Ron Meyer’s Easter party, then added presciently, “It’s because he knows he’s out.”

Indeed, the concensus was that Zucker’s charm offensive was really a defensive maneuver. It included taking full and sole responsibility for NBC broadcast network’s recent years in the ratings cellar. And failing to fire programming chief Ben Silverman a year earlier (though the boss still defended hiring that putz in the first place). And believing he could “reinvent” pilot season by getting away with spending little on new show development last year (though he defends spending heavily on this year’s pilot season). And installing Conan as Jay’s successor in late night wheen Leno was #1 and then putting Leno in primetime (though he defends replacing O’Brien as host of The Tonight Show).

Zucker was a wunderkind executive producer of The Today Show when, in December 2000, he was named NBC entertainment president to replace Garth Ancier, following a shaky start for the network that fall. But there were plenty of shaky fall launches for NBC under Zucker’s watch as NBC slipped from No. 1 to No. 4 in the ratings and failed to launch big noisy hit shows to succeed Friends and ER. Instead, Zucker embraced cheap and schlocky reality TV that undermined NBC’s quality brand. After a brief stint learning the ropes of the entertainment division where his biggest contribution was “supersizing” the network’s established Thursday comedies, Zucker quickly and surprisingly moved out and up. Eventually he replaced Bob Wright as CEO of NBC Universal. In that position, he presided over the downfall of the NBC broadcast network. He still can’t get it right. Even after spending enormously on primetime scripted development for this fall, NBC’s new lineup has been a mixed bag so far, with newcomers like The Event and Outsourced showing promise while Undercovers and Chase are lagging behind.

With nothing good to report ever about NBC Entertainment, Zucker liked to take credit for growing NBCU’s empire. The farflung cable division run by Bonnie Hammer remains a big revenue driver, providing 80% of NBCU’s $2.3 billion in profits for last year. But, really, Zucker by buying up cable properties (Oxygen, The Weather Channel, etc) has just been following the cable road mapped out by predeccessor Bob Wright to counter broadcast’s steep slide — yet taking credit for reinventing the wheel that drove NBCU there.

3RD UPDATE 8:10 AM: Still, the timing is a shocker. How bizarre that Zucker made the announcement to his staff this morning even though Comcast won’t clear regulatory hurdles until First Quarter 2011 at the earliest. (There’ve been considerable delays dragging out the deal approval process which was supposed to close by the end of Fourth Quarter 2010.) That makes Zucker not just a lame duck, but a sitting duck at the Big Media company. ”We’re all in shock,” an insider told me before news of the Zucker-Burke meeting got out. ”They must have fired him. He sent out a note to the staff along the lines of ‘I’ve loved my time here and it’s time for me to go.’” In fact, senior staff received word directly from Zucker about 30 minutes before the email went out wide to NBCU. (See email below.) One NBCU exec I spoke with this morning had just dealt with Zucker the day before. ”I spoke to him on other topics and he gave no indication. He didn’t seem depressed. It was business as usual.” The news first broke early this morning on CNBC which reported that Jeff Zucker will step down as CEO of NBC Universal after the merger with Comcast. CNBC has a history as the in-house clearinghouse for news about NBCU, GE, and now Comcast.

Here’s the email that Zucker sent to NBCU staff:

From: Zucker, Jeff (NBC Universal)
Sent: Friday, September 24, 2010 10:58 AM
To: NBC Universal Employee Communications (NBC Universal)
Subject: A Note from Jeff Zucker

September 24, 2010

Well, the time has come. This time, to tell you a little news about me.

When Comcast assumes control of NBC Universal, I will leave the company.

It has not been an easy or simple decision. I have spent my entire adult life here, more than 24 years. This is the only place I have ever worked. The only professional thing I have ever known. I met my wife here, enjoyed the birth of our four children in that time, worked in almost every division of the company. And forged relationships, both professional and personal, that will last a lifetime.

I remember, vividly, the first day I came to work here in August, 1986. I walked to work at 30 Rockefeller Plaza that day; it was humid and my shirt was soaking by the time I got there. In the years since, I have enjoyed nothing but sheer pleasure in having the names NBC and Universal on my business cards. Sure, there have been ups and downs in the last quarter century. But when I step back, and think about what we’ve been through, I feel nothing but pride and joy. It has been a great run and I’ve been incredibly fortunate.

Now, it is clear to me that this is the right decision for me and for the company. Comcast will be a great new steward, just as GE has been, and they deserve the chance to implement their own vision.

I am proud that they will inherit a company in very good shape, with almost every one of our divisions enjoying their best year ever. The current strength of the company is a tribute to every one of you and the terrific leadership team that is in place.

We’ll talk more about the shape of the company in the months ahead. For now, I just wanted you to know my plans. I won’t be going anywhere until the day the deal closes, and that day is still months away. There is plenty left to do, and we have an obligation to each other to maintain what we have already built. I will continue to approach everything we do with the long-term interest of the company in mind, just as I always have; I know no other way.

I don’t yet know what my future will bring. I’ve spent the last 24 years thinking only about NBC Universal, and never contemplated anything else. I haven’t even begun to think about the next chapter. But I wanted to be honest with you about this news as soon as I could.

I love NBC Universal. And always will. And I am grateful to each of you.

My most heartfelt thanks.

Editor-in-Chief Nikki Finke - tip her here.