Facebook (FB) CEO Mark Zuckerberg, who believes actions speak louder than words, is going to have to open his mouth Tuesday afternoon at the annual TechCrunch conference in San Francisco. He has little choice.

Investors have wanted to hang Zuckerberg by his hoodie strings following the social network's botched IPO, the subsequent heavy insider selling, and the emerging questions about plans for the mobile sector. And let's not forget the lingering worries about the company's utility as an advertising vehicle.

This is a change from Zuckerberg's previous position, which was that he couldn't be bothered with such concerns. So far, he has not shown that he has a knack for inspiring people. His recent pledge to hold onto shares of Facebook for a year was meaningless, given his net worth of about $12.1 billion. Unlike the rest of us, he can afford to have a Warren Buffett investment time frame of "forever."

The wunderkind will also need to address the "brain drain" at Facebook in the wake of the IPO, which is more extensive than some pundits had expected. The bloom is off Facebook's rose. It recently reported its first quarter-to-quarter revenue decline in at least two years, raising questions about its growth prospects. Wall Street is eagerly looking for the next big post-Facebook thing.

"The grim reality of being public ...  has set in," writes Mike Isaac on AllThingsD. "Despite the continued insistent focus on the long-term, Zuckerberg needs to address the here-and-now, what Facebook can do in the short-term."

Expect every minute detail of Zuckerberg's speech to be dissected -- ranging from his dress (hoodie or suit) to the tone of his voice (cheerful or serious) -- as if it were a biblical pronouncement. Zuckerberg will have to say something meaningful at TechCrunch, even if it does not include earnings guidance. Otherwise, Facebook shares will tumble even further into the financial abyss.

Jonathan Berr does not own shares of the listed stocks. Follow him on Twitter@jdberr.