The SXSWi keynote address of Facebook CEO Mark Zuckerberg had the Austin Convention Center room packed with an audience eager to hear what he had to say in the on-stage interview with BusinessWeek’s Sarah Lacy.

The interview wasn’t exactly what the audience would have expected, as Zuckerberg wasn’t given the chance to properly respond to questions he had been asked, but leaving all that aside, he did manage to say something about Facebook, Beacon, Microsoft and other matters.

Zuckerberg didn’t exactly end up giving first time info on Facebook’s latest plans or achievements, except maybe for the launch of a French version of the site, one week after the German version was also announced.

The 24-year old billionaire stated off by answering to one world-revolving question: “Did you ever think that people would be using Facebook to revolt against the government of Colombia?”, referring to the Spanish version of the site. The world’s youngest billionaire replied: “The thing that we are trying to do at Facebook is just help people communicate and connect.”

Moving on from ‘critical’ questions to things actually concerning Facebook, Zuckerberg got to talk about a more ‘delicate’ matter: Beacon. Delicate indeed, as one of the audience members shouted “Beacon sucks” right before he got to talk about it.

“Thank you”, Facebook CEO replied, adding in a more serious note that “we probably got a little ahead of ourselves and said we had more of it figured out than we actually did,” and admitting to making a lot of mistakes: “We’re still learning as a company.”

On the $15 billion the company has been valued to after the Microsoft deal, Zuckerberg commented they wanted as little dilution as possible and to raise money in favorable terms, and said the deal was going well. On a more relaxed note, he also made one remark for the audience’s delight: “Some people wanted the deal, and some people didn’t. We made some management changes,” he said, also referring to the departure of Owen Van Natta, who was the chief revenue officer for Facebook.

Referring to the company’s new chief operating officer, Sheryl Sandberg, the Facebook CEO said: “We’d been looking for someone who could help us scale our operations…it’s growing really quickly and so having someone who can help us scale is just going to be very important for the coming years.”

As for the “iTunes killer” everyone has been talking about, Zuckergerg wasn’t ready to confirm anything, except maybe for the talks that they have with a lot of companies all the time, and that there are music applications of Facebook already, but about a music service, he simply had “nothing to talk about right now.”

With only 10 minutes before the end of the interview, Lacy gave up the mike for the audience and ended up telling Zuckerberg she was sorry for the one-hour torture she submitted him to: “I don’t think this has been that painfull!” he replied.