Yao Jianjiang, vice president of Ku6.com, a leading video website in China, wrote on his microblog that Facebook's entry into China would lead to its inevitable retreat. This may seem like a radical preview but given the decline of social media players in China, Facebook may find it hard to strike gold here.

The differences in culture and Web users' behavioral habits seem to be an insurmountable barrier. Users around the world have begun to criticize Facebook's violation of privacy. The Chinese tend to be even more conservative, with a stronger sense of self-protection and privacy.

This also partly explains why local social media giants have already begun to see their memberships drop.

With claimed membership up to 100 million, providers like renren.com and kaixin001.com better understand Chinese users' demands, and have secured loyal and vast user groups. It would be difficult for Facebook to break this high rampart.

Facebook does have one major strength that Chinese competitors lack: Connecting the whole world. Currently, looking at Facebook's global landscape, several markets are blank, including China.

Zuckerberg has expressed his interest in filling in these blanks, but a bulging wallet and an ambitious mind are surely not enough.

Before setting out, Zuckerberg has to first figure what kind of benefits he can really bring to the Chinese, and if he can abide by local rules.