RANCHO PALOS VERDES, Calif. (MarketWatch) -- Facebook Inc.'s 26-year-old chief executive, Mark Zuckerberg, literally squirmed in his seat, took off his famous hoodie sweatshirt and had a Richard Nixon moment under the grilling of two of the hosts of the All Things D Conference.

As D8 co-host and BoomTown blogger Kara Swisher asked him if recent unflattering stories of the early days of Facebook accurately portrayed him, he squirmed.

"When I was 18 or 19 years old, I did a lot of stupid things," he said. "I don't want to make an excuse for that. I'm really sorry that I did them."

Sweat literally dripped from his face as he mostly avoided giving specific answers about the backlash stemming from the popular social network's recent privacy changes that caused ire among users. Zuckerberg also dodged questions about how the backlash stemming from another recent privacy uproar affected him personally. See Tech Tales column on Facebook's recent issues.

"A lot of stuff happened along the way," Zuckerberg responded, briefly recounting the well-known story of Facebook's earliest roots in a dorm at Harvard University and its subsequent move to Silicon Valley. In the last few years, Facebook has exploded to nearly 500 million users.

Facebook's Zuckerberg alongside an image of Richard Nixon during the famous Kennedy-Nixon TV debate in September 1960.

When Zuckerberg wiped sweat from his face, then took off his black sweatshirt, Swisher examined the hoodie, revealing Facebook logo inside. "This is a great moment in Internet history," she said, before examining the hoodie and joking about a secret cult.

The interview was rich in irony. For the CEO of a company that wants everyone to share information, Zuckerberg clearly did not like talking about himself in front of some of the tech industry's biggest movers and shakers. Just like a teenager who posts something silly on Facebook that he or she will regret later, Zuckerberg did not like being reminded of what may have been some of his less-than-finer moments.

Not specifically mentioned, but easily inferred, were recent tales in the blogosphere about instant messages purportedly from a 19-year-old Zuckerberg to a friend who asked him how he gathered information about his users. "They trust me," comes the reply. "Dumb Fxxxs."

And coming out next week is "The Facebook Effect," a book that also recounts the site's early days, by journalist David Kirkpatrick. Separately, an unflattering movie is in the works.

Zuckerberg is still young. He deserves kudos for getting on the stage and at least saying he is sorry for some of his past moves and that privacy is important to Facebook.

The room was clearly sympathetic to the young CEO being grilled by two veteran journalists, Swisher and Walt Mossberg of The Wall Street Journal, who actually were tactful and kind if persistent in trying to get answers to their questions.

But Zuckerberg's evasive and rambling answers about privacy and the company's revenue model were irritating. He did not seem any closer to a willingness to change Facebook's privacy controls so that they are set to the highest levels of protection by default. He even predicted that the current privacy brouhaha could ultimately end up as an all-but-forgotten footnote, just like the uproar when the "news feed" first emerged; it's now one of Facebook's most popular features.

In a moment of rare precision early on Wednesday evening, Zuckerberg did say there have been misconceptions about Facebook's privacy policy. "We recommend you share only with your friends all your really sensitive stuff," he said.

So, while Zuckerberg may be of a generation prone to oversharing all the moments of their lives, it was pretty amusing when he said: "I wish that no one made a movie about me when I was alive."