Summary Box: Zuck _ Facebook has overcome hurdles
DON'T WORRY: Facebook CEO Mark Zuckerberg is acknowledging concerns about his company's stock performance, but he says Facebook has survived troubles before.
THE FORUM: He spoke to a standing-room-only audience at a tech conference in San Francisco. It's his first interview since the company's rocky initial public offering in May.
RESPONSE: Facebook's stock went up in after-hours trading after he began speaking.