Facebook Mark Zuckerberg Japan Prime Minister Yoshihiko Noda mobile hack Facebook's chief executive is now serving in another capacity: its official ambassador. Mark Zuckerberg, who was most recently spotted in China, is visiting Japan and, with camera flashes blazing, had a brief meeting with a star-struck Prime Minister Yoshihiko Noda. Zuckerberg told Noda that the tsunami that struck the nation inspired him to find ways that the social network can help people in natural disasters. Last month, Facebook rolled out a "Disaster Message Board" in Japan to help people find each other during emergencies. For years Facebook lagged behind other social networks in Japan. But it doubled its users after last year's tsunami and jumped into the No. 1 position ahead of Twitter and domestic competitor Mixi. Noda said it was odd to meet the entrepreneur who was made world famous in the hit film "The Social Network." Zuckerberg laughed and shrugged off Hollywood's less-than-flattering portrayal. "Very different," he said. A Facebook spokeswoman declined to comment on the meeting, but said Zuckerberg is in Tokyo for a mobile hack event. "With more than 10 million people on Facebook in Japan, a robust developer community, and a sophisticated mobile market, Japan is an important country for Facebook," she wrote in an email. Mark is in Japan to attend Mobile Hack Tokyo, and to observe and learn from the Japanese mobile developer community. Some 160 developers are expected to attend, she added. The mobile hack event is an opportunity for Japanese mobile developers to hack with Facebook's developer relations team. It's part of the Mobile Hack Asia Roadshow that is making stops in Singapore, Hong Kong and Seoul. Facebook is on the verge of a $100-billion initial public stock offering that will make it one of the most richly valued companies in the world. Facebook has more than 845 million users around the world. Europe is the largest market for advertising revenue outside of the United States and Canada, according to the company's filing with the U.S. Securities and Exchange Commission. Facebook CEO Mark Zuckerberg spotted on vacation in China